130.blob转file
/**
* @param { blob } blob
* @param { string } fileName
*/
export const blobToFile = (blob, fileName) => {
blob.lastModifiedDate = new Date();
blob.name = fileName;
return blob;
};
131.file转base64
/**
* @param { * } file 图片文件
*/
export const fileToBase64 = file => {
let reader = new FileReader();
reader.readAsDataURL(file);
reader.onload = function (e) {
return e.target.result
};
};
132.递归生成树形结构
export function getTreeData(data, pid, pidName = 'parentId', idName = 'id', childrenName = 'children', key) {
let arr = [];
for (let i = 0; i < data.length; i++) {
if (data[i][pidName] == pid) {
data[i].key = data[i][idName];
data[i][childrenName] = getTreeData(data, data[i][idName], pidName, idName, childrenName);
arr.push(data[i]);
}
}
return arr;
}
133.遍历树节点
export function foreachTree(data, childrenName = 'children', callback) {
for (let i = 0; i < data.length; i++) {
callback(data[i]);
if (data[i][childrenName] && data[i][childrenName].length > 0) {
foreachTree(data[i][childrenName], childrenName, callback);
}
}
}
134.追溯父节点
export function traceParentNode(pid, data, rootPid, pidName = 'parentId', idName = 'id', childrenName = 'children') {
let arr = [];
foreachTree(data, childrenName, (node) => {
if (node[idName] == pid) {
arr.push(node);
if (node[pidName] != rootPid) {
arr = arr.concat(traceParentNode(node[pidName], data, rootPid, pidName, idName));
}
}
});
return arr;
}
135.寻找所有子节点
export function traceChildNode(id, data, pidName = 'parentId', idName = 'id', childrenName = 'children') {
let arr = [];
foreachTree(data, childrenName, (node) => {
if (node[pidName] == id) {
arr.push(node);
arr = arr.concat(traceChildNode(node[idName], data, pidName, idName, childrenName));
}
});
return arr;
}
136.根据pid生成树形结构
/**
* @param { object } items 后台获取的数据
* @param { * } id 数据中的id
* @param { * } link 生成树形结构的依据
*/
export const createTree = (items, id = null, link = 'pid') =>{
items.filter(item => item[link] === id).map(item => ({ ...item, children: createTree(items, item.id) }));
};
137.查询数组中是否存在某个元素并返回元素第一次出现的下标
/**
* @param {*} item
* @param { array } data
*/
export function inArray(item, data) {
for (let i = 0; i < data.length; i++) {
if (item === data[i]) {
return i;
}
}
return -1;
}
138.Windows根据详细版本号判断当前系统名称
/**
* @param { string } osVersion
*/
export function OutOsName(osVersion) {
if(!osVersion){
return
}
let str = osVersion.substr(0, 3);
if (str === "5.0") {
return "Win 2000"
} else if (str === "5.1") {
return "Win XP"
} else if (str === "5.2") {
return "Win XP64"
} else if (str === "6.0") {
return "Win Vista"
} else if (str === "6.1") {
return "Win 7"
} else if (str === "6.2") {
return "Win 8"
} else if (str === "6.3") {
return "Win 8.1"
} else if (str === "10.") {
return "Win 10"
} else {
return "Win"
}
}
139.判断手机是Andoird还是IOS
/**
* 0: ios
* 1: android
* 2: 其它
*/
export function getOSType() {
let u = navigator.userAgent, app = navigator.appVersion;
let isAndroid = u.indexOf('Android') > -1 || u.indexOf('Linux') > -1;
let isIOS = !!u.match(/\(i[^;]+;( U;)? CPU.+Mac OS X/);
if (isIOS) {
return 0;
}
if (isAndroid) {
return 1;
}
return 2;
}
140.函数防抖
/**
* @param { function } func
* @param { number } wait 延迟执行毫秒数
* @param { boolean } immediate true 表立即执行,false 表非立即执行
*/
export function debounce(func,wait,immediate) {
let timeout;
return function () {
let context = this;
let args = arguments;
if (timeout) clearTimeout(timeout);
if (immediate) {
let callNow = !timeout;
timeout = setTimeout(() => {
timeout = null;
}, wait);
if (callNow) func.apply(context, args)
}
else {
timeout = setTimeout(() => {
func.apply(context, args)
}, wait);
}
}
}
145.函数节流
/**
* @param { function } func 函数
* @param { number } wait 延迟执行毫秒数
* @param { number } type 1 表时间戳版,2 表定时器版
*/
export function throttle(func, wait ,type) {
let previous, timeout;
if(type===1){
previous = 0;
}else if(type===2){
timeout = null;
}
return function() {
let context = this;
let args = arguments;
if(type===1){
let now = Date.now();
if (now - previous > wait) {
func.apply(context, args);
previous = now;
}
}else if(type===2){
if (!timeout) {
timeout = setTimeout(() => {
timeout = null;
func.apply(context, args)
}, wait)
}
}
}
}
146.判断数据类型
/**
* @param {*} target
*/
export function type(target) {
let ret = typeof(target);
let template = {
"[object Array]": "array",
"[object Object]":"object",
"[object Number]":"number - object",
"[object Boolean]":"boolean - object",
"[object String]":'string-object'
};
if(target === null) {
return 'null';
}else if(ret == "object"){
let str = Object.prototype.toString.call(target);
return template[str];
}else{
return ret;
}
}
147.生成指定范围随机数
/**
* @param { number } min
* @param { number } max
*/
export const RandomNum = (min, max) => Math.floor(Math.random() * (max - min + 1)) + min;
148.数组乱序
/**
* @param {array} arr
*/
export function arrScrambling(arr) {
let array = arr;
let index = array.length;
while (index) {
index -= 1;
let randomIndex = Math.floor(Math.random() * index);
let middleware = array[index];
array[index] = array[randomIndex];
array[randomIndex] = middleware
}
return array
}
150.数组交集
/**
* @param { array} arr1
* @param { array } arr2
*/
export const similarity = (arr1, arr2) => arr1.filter(v => arr2.includes(v));
151.数组中某元素出现的次数
/**
* @param { array } arr
* @param {*} value
*/
export function countOccurrences(arr, value) {
return arr.reduce((a, v) => v === value ? a + 1 : a + 0, 0);
}
152.加法函数(精度丢失问题)
/**
* @param { number } arg1
* @param { number } arg2
*/
export function add(arg1, arg2) {
let r1, r2, m;
try { r1 = arg1.toString().split(".")[1].length } catch (e) { r1 = 0 }
try { r2 = arg2.toString().split(".")[1].length } catch (e) { r2 = 0 }
m = Math.pow(10, Math.max(r1, r2));
return (arg1 * m + arg2 * m) / m
}
153.减法函数(精度丢失问题)
/**
* @param { number } arg1
* @param { number } arg2
*/
export function sub(arg1, arg2) {
let r1, r2, m, n;
try { r1 = arg1.toString().split(".")[1].length } catch (e) { r1 = 0 }
try { r2 = arg2.toString().split(".")[1].length } catch (e) { r2 = 0 }
m = Math.pow(10, Math.max(r1, r2));
n = (r1 >= r2) ? r1 : r2;
return Number(((arg1 * m - arg2 * m) / m).toFixed(n));
}
154.除法函数(精度丢失问题)
/**
* @param { number } num1
* @param { number } num2
*/
export function division(num1,num2){
let t1,t2,r1,r2;
try{
t1 = num1.toString().split('.')[1].length;
}catch(e){
t1 = 0;
}
try{
t2=num2.toString().split(".")[1].length;
}catch(e){
t2=0;
}
r1=Number(num1.toString().replace(".",""));
r2=Number(num2.toString().replace(".",""));
return (r1/r2)*Math.pow(10,t2-t1);
}
155.乘法函数(精度丢失问题)
/**
* @param { number } num1
* @param { number } num2
*/
export function mcl(num1,num2){
let m=0,s1=num1.toString(),s2=num2.toString();
try{m+=s1.split(".")[1].length}catch(e){}
try{m+=s2.split(".")[1].length}catch(e){}
return Number(s1.replace(".",""))*Number(s2.replace(".",""))/Math.pow(10,m);
}
156.递归优化(尾递归)
/**
* @param { function } f
*/
export function tco(f) {
let value;
let active = false;
let accumulated = [];
return function accumulator() {
accumulated.push(arguments);
if (!active) {
active = true;
while (accumulated.length) {
value = f.apply(this, accumulated.shift());
}
active = false;
return value;
}
};
}
157.生成随机整数
export function randomNumInteger(min, max) {
switch (arguments.length) {
case 1:
return parseInt(Math.random() * min + 1, 10);
case 2:
return parseInt(Math.random() * (max - min + 1) + min, 10);
default:
return 0
}
}
158.去除空格
/**
* @param { string } str 待处理字符串
* @param { number } type 去除空格类型 1-所有空格 2-前后空格 3-前空格 4-后空格 默认为1
*/
export function trim(str, type = 1) {
if (type && type !== 1 && type !== 2 && type !== 3 && type !== 4) return;
switch (type) {
case 1:
return str.replace(/\s/g, "");
case 2:
return str.replace(/(^\s)|(\s*$)/g, "");
case 3:
return str.replace(/(^\s)/g, "");
case 4:
return str.replace(/(\s$)/g, "");
default:
return str;
}
}
159.大小写转换
/**
* @param { string } str 待转换的字符串
* @param { number } type 1-全大写 2-全小写 3-首字母大写 其他-不转换
*/
export function turnCase(str, type) {
switch (type) {
case 1:
return str.toUpperCase();
case 2:
return str.toLowerCase();
case 3:
return str[0].toUpperCase() + str.substr(1).toLowerCase();
default:
return str;
}
}
160.随机16进制颜色 hexColor
/**
* 方法一
*/
export function hexColor() {
let str = '#';
let arr = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 'A', 'B', 'C', 'D', 'E', 'F'];
for (let i = 0; i < 6; i++) {
let index = Number.parseInt((Math.random() * 16).toString());
str += arr[index]
}
return str;
}
161.随机16进制颜色 randomHexColorCode
/**
* 方法二
*/
export const randomHexColorCode = () => {
let n = (Math.random() * 0xfffff * 1000000).toString(16);
return '#' + n.slice(0, 6);
};
162.转义html(防XSS攻击)
export const escapeHTML = str =>{
str.replace(
/[&<>'"]/g,
tag =>
({
'&': '&',
'<': '<',
'>': '>',
"'": ''',
'"': '"'
}[tag] || tag)
);
};
163.检测移动/PC设备
export const detectDeviceType = () => { return /Android|webOS|iPhone|iPad|iPod|BlackBerry|IEMobile|Opera Mini/i.test(navigator.userAgent) ? 'Mobile' : 'Desktop'; };
164.隐藏所有指定标签
/**
* 例: hide(document.querySelectorAll('img'))
*/
export const hideTag = (...el) => [...el].forEach(e => (e.style.display = 'none'));
165.返回指定元素的生效样式
/**
* @param { element} el 元素节点
* @param { string } ruleName 指定元素的名称
*/
export const getStyle = (el, ruleName) => getComputedStyle(el)[ruleName];
166.检查是否包含子元素
/**
* @param { element } parent
* @param { element } child
* 例:elementContains(document.querySelector('head'), document.querySelector('title')); // true
*/
export const elementContains = (parent, child) => parent !== child && parent.contains(child);
167.数字超过规定大小加上加号“+”,如数字超过99显示99+
/**
* @param { number } val 输入的数字
* @param { number } maxNum 数字规定界限
*/
export const outOfNum = (val, maxNum) =>{
val = val ? val-0 :0;
if (val > maxNum ) {
return `${maxNum}+`
}else{
return val;
}
};
168.如何隐藏所有指定的元素
const hide = (el) => Array.from(el).forEach(e => (e.style.display = 'none'));
// 事例:隐藏页面上所有`<img>`元素?
hide(document.querySelectorAll('img'))
169.如何检查元素是否具有指定的类?
页面DOM里的每个节点上都有一个classList对象,程序员可以使用里面的方法新增、删除、修改节点上的CSS类。使用classList,程序员还可以用它来判断某个节点是否被赋予了某个CSS类。
const hasClass = (el, className) => el.classList.contains(className)
// 事例
hasClass(document.querySelector('p.special'), 'special') // true
170.如何切换一个元素的类?
const toggleClass = (el, className) => el.classList.toggle(className)
// 事例 移除 p 具有类`special`的 special 类
toggleClass(document.querySelector('p.special'), 'special')
171.如何获取当前页面的滚动位置?
const getScrollPosition = (el = window) => ({
x: el.pageXOffset !== undefined ? el.pageXOffset : el.scrollLeft,
y: el.pageYOffset !== undefined ? el.pageYOffset : el.scrollTop
});
// 事例
getScrollPosition(); // {x: 0, y: 200}
172.如何平滑滚动到页面顶部
const scrollToTop = () => {
const c = document.documentElement.scrollTop || document.body.scrollTop;
if (c > 0) {
window.requestAnimationFrame(scrollToTop);
window.scrollTo(0, c - c / 8);
}
}
// 事例
scrollToTop()
window.requestAnimationFrame() 告诉浏览器——你希望执行一个动画,并且要求浏览器在下次重绘之前调用指定的回调函数更新动画。该方法需要传入一个回调函数作为参数,该回调函数会在浏览器下一次重绘之前执行。
requestAnimationFrame:优势:由系统决定回调函数的执行时机。60Hz的刷新频率,那么每次刷新的间隔中会执行一次回调函数,不会引起丢帧,不会卡顿。
window.requestAnimationFrame() 告诉浏览器——你希望执行一个动画,并且要求浏览器在下次重绘之前调用指定的回调函数更新动画。该方法需要传入一个回调函数作为参数,该回调函数会在浏览器下一次重绘之前执行。
requestAnimationFrame:优势:由系统决定回调函数的执行时机。60Hz的刷新频率,那么每次刷新的间隔中会执行一次回调函数,不会引起丢帧,不会卡顿。
173.如何检查父元素是否包含子元素?
const elementContains = (parent, child) => parent !== child && parent.contains(child);
// 事例
elementContains(document.querySelector('head'), document.querySelector('title'));
// true
elementContains(document.querySelector('body'), document.querySelector('body'));
// false
174.如何检查指定的元素在视口中是否可见?
const elementIsVisibleInViewport = (el, partiallyVisible = false) => {
const { top, left, bottom, right } = el.getBoundingClientRect();
const { innerHeight, innerWidth } = window;
return partiallyVisible
? ((top > 0 && top < innerHeight) || (bottom > 0 && bottom < innerHeight)) &&
((left > 0 && left < innerWidth) || (right > 0 && right < innerWidth))
: top >= 0 && left >= 0 && bottom <= innerHeight && right <= innerWidth;
};
// 事例
elementIsVisibleInViewport(el); // 需要左右可见
elementIsVisibleInViewport(el, true); // 需要全屏(上下左右)可以见
175.如何获取元素中的所有图像?
const getImages = (el, includeDuplicates = false) => {
const images = [...el.getElementsByTagName('img')].map(img => img.getAttribute('src'));
return includeDuplicates ? images : [...new Set(images)];
};
// 事例:includeDuplicates 为 true 表示需要排除重复元素
getImages(document, true); // ['image1.jpg', 'image2.png', 'image1.png', '...']
getImages(document, false); // ['image1.jpg', 'image2.png', '...']
176.如何确定设备是移动设备还是台式机/笔记本电脑?
const detectDeviceType = () =>
/Android|webOS|iPhone|iPad|iPod|BlackBerry|IEMobile|Opera Mini/i.test(navigator.userAgent)
? 'Mobile'
: 'Desktop';
// 事例
detectDeviceType(); // "Mobile" or "Desktop"
177.How to get the current URL?
const currentURL = () => window.location.href
// 事例
currentURL() // 'https://google.com'
178.如何创建一个包含当前URL参数的对象?
const getURLParameters = url =>
(url.match(/([^?=&]+)(=([^&]*))/g) || []).reduce(
(a, v) => ((a[v.slice(0, v.indexOf('='))] = v.slice(v.indexOf('=') + 1)), a),
{}
);
// 事例
getURLParameters('http://url.com/page?n=Adam&s=Smith'); // {n: 'Adam', s: 'Smith'}
getURLParameters('google.com'); // {}
179.如何将一组表单元素转化为对象?
const formToObject = form =>
Array.from(new FormData(form)).reduce(
(acc, [key, value]) => ({
...acc,
[key]: value
}),
{}
);
// 事例
formToObject(document.querySelector('#form'));
// { email: 'test@email.com', name: 'Test Name' }
180.如何从对象检索给定选择器指示的一组属性?
const get = (from, ...selectors) =>
[...selectors].map(s =>
s
.replace(/\[([^\[\]]*)\]/g, '.$1.')
.split('.')
.filter(t => t !== '')
.reduce((prev, cur) => prev && prev[cur], from)
);
const obj = { selector: { to: { val: 'val to select' } }, target: [1, 2, { a: 'test' }] };
// Example
get(obj, 'selector.to.val', 'target[0]', 'target[2].a');
// ['val to select', 1, 'test']
181.如何在等待指定时间后调用提供的函数?
const delay = (fn, wait, ...args) => setTimeout(fn, wait, ...args);
delay(
function(text) {
console.log(text);
},
1000,
'later'
);
// 1秒后打印 'later'
182.如何在给定元素上触发特定事件且能选择地传递自定义数据?
const triggerEvent = (el, eventType, detail) =>
el.dispatchEvent(new CustomEvent(eventType, { detail }));
// 事例
triggerEvent(document.getElementById('myId'), 'click');
triggerEvent(document.getElementById('myId'), 'click', { username: 'bob' });
自定义事件的函数有 Event、CustomEvent 和 dispatchEvent
// 向 window派发一个resize内置事件
window.dispatchEvent(new Event('resize'))
// 直接自定义事件,使用 Event 构造函数:
var event = new Event('build');
var elem = document.querySelector('#id')
// 监听事件
elem.addEventListener('build', function (e) { ... }, false);
// 触发事件.
elem.dispatchEvent(event);
CustomEvent 可以创建一个更高度自定义事件,还可以附带一些数据,具体用法如下:
var myEvent = new CustomEvent(eventname, options);
其中 options 可以是:
{
detail: {
...
},
bubbles: true, //是否冒泡
cancelable: false //是否取消默认事件
}
其中 detail 可以存放一些初始化的信息,可以在触发的时候调用。其他属性就是定义该事件是否具有冒泡等等功能。
内置的事件会由浏览器根据某些操作进行触发,自定义的事件就需要人工触发。
dispatchEvent 函数就是用来触发某个事件:
element.dispatchEvent(customEvent);
上面代码表示,在 element 上面触发 customEvent 这个事件。
// add an appropriate event listener
obj.addEventListener("cat", function(e) { process(e.detail) });
// create and dispatch the event
var event = new CustomEvent("cat", {"detail":{"hazcheeseburger":true}});
obj.dispatchEvent(event);
使用自定义事件需要注意兼容性问题,而使用 jQuery 就简单多了:
// 绑定自定义事件
$(element).on('myCustomEvent', function(){});
// 触发事件
$(element).trigger('myCustomEvent');
// 此外,你还可以在触发自定义事件时传递更多参数信息:
$( "p" ).on( "myCustomEvent", function( event, myName ) {
$( this ).text( myName + ", hi there!" );
});
$( "button" ).click(function () {
$( "p" ).trigger( "myCustomEvent", [ "John" ] );
});
183.如何从元素中移除事件监听器?
const off = (el, evt, fn, opts = false) => el.removeEventListener(evt, fn, opts);
const fn = () => console.log('!');
document.body.addEventListener('click', fn);
off(document.body, 'click', fn);
184.如何获得给定毫秒数的可读格式?
const formatDuration = ms => {
if (ms < 0) ms = -ms;
const time = {
day: Math.floor(ms / 86400000),
hour: Math.floor(ms / 3600000) % 24,
minute: Math.floor(ms / 60000) % 60,
second: Math.floor(ms / 1000) % 60,
millisecond: Math.floor(ms) % 1000
};
return Object.entries(time)
.filter(val => val[1] !== 0)
.map(([key, val]) => `${val} ${key}${val !== 1 ? 's' : ''}`)
.join(', ');
};
// 事例
formatDuration(1001); // '1 second, 1 millisecond'
formatDuration(34325055574);
// '397 days, 6 hours, 44 minutes, 15 seconds, 574 milliseconds'
185.如何获得两个日期之间的差异(以天为单位)?
const getDaysDiffBetweenDates = (dateInitial, dateFinal) =>
(dateFinal - dateInitial) / (1000 * 3600 * 24);
// 事例
getDaysDiffBetweenDates(new Date('2017-12-13'), new Date('2017-12-22')); // 9
186.如何向传递的URL发出GET请求?
const httpGet = (url, callback, err = console.error) => {
const request = new XMLHttpRequest();
request.open('GET', url, true);
request.onload = () => callback(request.responseText);
request.onerror = () => err(request);
request.send();
};
httpGet(
'https://jsonplaceholder.typicode.com/posts/1',
console.log
);
// {"userId": 1, "id": 1, "title": "sample title", "body": "my text"}
187.如何对传递的URL发出POST请求?
const httpPost = (url, data, callback, err = console.error) => {
const request = new XMLHttpRequest();
request.open('POST', url, true);
request.setRequestHeader('Content-type', 'application/json; charset=utf-8');
request.onload = () => callback(request.responseText);
request.onerror = () => err(request);
request.send(data);
};
const newPost = {
userId: 1,
id: 1337,
title: 'Foo',
body: 'bar bar bar'
};
const data = JSON.stringify(newPost);
httpPost(
'https://jsonplaceholder.typicode.com/posts',
data,
console.log
);
// {"userId": 1, "id": 1337, "title": "Foo", "body": "bar bar bar"}
188.如何为指定选择器创建具有指定范围,步长和持续时间的计数器?
const counter = (selector, start, end, step = 1, duration = 2000) => {
let current = start,
_step = (end - start) * step < 0 ? -step : step,
timer = setInterval(() => {
current += _step;
document.querySelector(selector).innerHTML = current;
if (current >= end) document.querySelector(selector).innerHTML = end;
if (current >= end) clearInterval(timer);
}, Math.abs(Math.floor(duration / (end - start))));
return timer;
};
// 事例
counter('#my-id', 1, 1000, 5, 2000);
// 让 `id=“my-id”`的元素创建一个2秒计时器
189.如何将字符串复制到剪贴板?
const el = document.createElement('textarea');
el.value = str;
el.setAttribute('readonly', '');
el.style.position = 'absolute';
el.style.left = '-9999px';
document.body.appendChild(el);
const selected =
document.getSelection().rangeCount > 0 ? document.getSelection().getRangeAt(0) : false;
el.select();
document.execCommand('copy');
document.body.removeChild(el);
if (selected) {
document.getSelection().removeAllRanges();
document.getSelection().addRange(selected);
}
};
// 事例
copyToClipboard('Lorem ipsum');
// 'Lorem ipsum' copied to clipboard
190.如何确定页面的浏览器选项卡是否聚焦?
const isBrowserTabFocused = () => !document.hidden;
// 事例
isBrowserTabFocused(); // true
191.如何创建目录(如果不存在)?
const fs = require('fs');
const createDirIfNotExists = dir => (!fs.existsSync(dir) ? fs.mkdirSync(dir) : undefined);
// 事例
createDirIfNotExists('test');
这里面的方法大都挺实用,可以解决很多开发过程问题,大家就好好利用起来吧。
192.日期型函数封装
function formatTime(date) {
if(!!date){
if(!(date instanceof Date))
date = new Date(date);
var month = date.getMonth() + 1
var day = date.getDate()
return `${month}月${day}日`;
}
}
function formatDay(date) {
if(!!date){
var year = date.getFullYear()
var month = date.getMonth() + 1
var day = date.getDate()
return [year, month, day].map(formatNumber).join('-');
}
}
function formatDay2(date) {
if(!!date){
var year = date.getFullYear()
var month = date.getMonth() + 1
var day = date.getDate()
return [year, month, day].map(formatNumber).join('/');
}
}
function formatWeek(date){
if(!!date){
var day = date.getDay();
switch (day) {
case 0:
return '周日'
break;
case 1:
return '周一'
break;
case 2:
return '周二'
break;
case 3:
return '周三'
break;
case 4:
return '周四'
break;
case 5:
return '周五'
break;
case 6:
return '周六'
break;
}
}
}
function formatHour(date){
if(!!date){
var hour = new Date(date).getHours();
var minute = new Date(date).getMinutes();
return [hour, minute].map(formatNumber).join(':');
}
}
function timestamp(date, divisor=1000){
if(date == undefined){
return;
}else if(typeof date == 'number'){
return Math.floor(date/divisor);
}else if(typeof date == 'string'){
var strs = date.split(/[^0-9]/);
return Math.floor(+new Date(strs[0] || 0,(strs[1] || 0)-1,strs[2] || 0,strs[3] || 0,strs[4] || 0,strs[5] || 0)/divisor);
}else if(Date.prototype.isPrototypeOf(date)){
return Math.floor(+date/divisor);
}
}
function detimestamp(date){
if(!!date){
return new Date(date*1000);
}
}
function formatNumber(n) {//给在0-9的日期加上0
n = n.toString()
return n[1] ? n : '0' + n
}
module.exports = {
formatTime: formatTime,
formatDay: formatDay,
formatDay2: formatDay2,
formatHour: formatHour,
formatWeek: formatWeek,
timestamp: timestamp,
detimestamp: detimestamp
}
193.时间戳转时间
/**
* 时间戳转化为年 月 日 时 分 秒
* number: 传入时间戳
* format:返回格式,支持自定义,但参数必须与formateArr里保持一致
*/
function formatTime(number,format) {
var formateArr = ['Y','M','D','h','m','s'];
var returnArr = [];
var date = new Date(number * 1000);
returnArr.push(date.getFullYear());
returnArr.push(formatNumber(date.getMonth() + 1));
returnArr.push(formatNumber(date.getDate()));
returnArr.push(formatNumber(date.getHours()));
returnArr.push(formatNumber(date.getMinutes()));
returnArr.push(formatNumber(date.getSeconds()));
for (var i in returnArr)
{
format = format.replace(formateArr[i], returnArr[i]);
}
return format;
}
//数据转化
function formatNumber(n) {
n = n.toString()
return n[1] ? n : '0' + n
}
调用示例:
var sjc = 1488481383;//时间戳
console.log(time.formatTime(sjc,'Y/M/D h:m:s'));//转换为日期:2017/03/03 03:03:03
console.log(time.formatTime(sjc, 'h:m'));//转换为日期:03:03
194.js中获取上下文路径
js中获取上下文路径
//js获取项目根路径,如: http://localhost:8083/uimcardprj
function getRootPath(){
//获取当前网址,如: http://localhost:8083/uimcardprj/share/meun.jsp
var curWwwPath=window.document.location.href;
//获取主机地址之后的目录,如: uimcardprj/share/meun.jsp
var pathName=window.document.location.pathname;
var pos=curWwwPath.indexOf(pathName);
//获取主机地址,如: http://localhost:8083
var localhostPaht=curWwwPath.substring(0,pos);
//获取带"/"的项目名,如:/uimcardprj
var projectName=pathName.substring(0,pathName.substr(1).indexOf('/')+1);
return(localhostPaht+projectName);
}
195.JS大小转化B KB MB GB的转化方法
function conver(limit){
var size = "";
if( limit < 0.1 * 1024 ){ //如果小于0.1KB转化成B
size = limit.toFixed(2) + "B";
}else if(limit < 0.1 * 1024 * 1024 ){//如果小于0.1MB转化成KB
size = (limit / 1024).toFixed(2) + "KB";
}else if(limit < 0.1 * 1024 * 1024 * 1024){ //如果小于0.1GB转化成MB
size = (limit / (1024 * 1024)).toFixed(2) + "MB";
}else{ //其他转化成GB
size = (limit / (1024 * 1024 * 1024)).toFixed(2) + "GB";
}
var sizestr = size + "";
var len = sizestr.indexOf("\.");
var dec = sizestr.substr(len + 1, 2);
if(dec == "00"){//当小数点后为00时 去掉小数部分
return sizestr.substring(0,len) + sizestr.substr(len + 3,2);
}
return sizestr;
}
196.js全屏和退出全屏
function fullScreen() {
var el = document.documentElement;
var rfs = el.requestFullScreen || el.webkitRequestFullScreen || el.mozRequestFullScreen || el.msRequestFullScreen;
//typeof rfs != "undefined" && rfs
if (rfs) {
rfs.call(el);
} else if (typeof window.ActiveXObject !== "undefined") {
//for IE,这里其实就是模拟了按下键盘的F11,使浏览器全屏
var wscript = new ActiveXObject("WScript.Shell");
if (wscript != null) {
wscript.SendKeys("{F11}");
}
}
}
//退出全屏
function exitScreen() {
var el = document;
var cfs = el.cancelFullScreen || el.webkitCancelFullScreen || el.mozCancelFullScreen || el.exitFullScreen;
//typeof cfs != "undefined" && cfs
if (cfs) {
cfs.call(el);
} else if (typeof window.ActiveXObject !== "undefined") {
//for IE,这里和fullScreen相同,模拟按下F11键退出全屏
var wscript = new ActiveXObject("WScript.Shell");
if (wscript != null) {
wscript.SendKeys("{F11}");
}
}
}
197.格式化时间,转化为几分钟前,几秒钟前
/**
* 格式化时间,转化为几分钟前,几秒钟前
* @param timestamp 时间戳,单位是毫秒
*/
function timeFormat(timestamp) {
var mistiming = Math.round((Date.now() - timestamp) / 1000);
var arrr = ['年', '个月', '星期', '天', '小时', '分钟', '秒'];
var arrn = [31536000, 2592000, 604800, 86400, 3600, 60, 1];
for (var i = 0; i < arrn.length; i++) {
var inm = Math.floor(mistiming / arrn[i]);
if (inm != 0) {
return inm + arrr[i] + '前';
}
}
}
198 获取n天之前的日期 getDaysBeforeDate(10) 10天前
/**
* 获取n天之前的日期 getDaysBeforeDate(10) 10天前
* @param day 天数
*/
function getDaysBeforeDate(day) {
var date = new Date(),
timestamp, newDate;
timestamp = date.getTime();
// 获取三天前的日期
newDate = new Date(timestamp - day * 24 * 3600 * 1000);
var year = newDate.getFullYear();
// 月+1是因为js中月份是按0开始的
var month = newDate.getMonth() + 1;
var day = newDate.getDate();
if (day < 10) { // 如果日小于10,前面拼接0
day = '0' + day;
}
if (month < 10) { // 如果月小于10,前面拼接0
month = '0' + month;
}
return [year, month, day].join('/');
}
199.获取跳转的classId,通过hash方式获取
/**
* 获取跳转的classId,通过hash方式获取
* @return 返回值
*/
$scope.getQueryString = function() {
var url= {},
a = '';
(a = window.location.search.substr(1)) || (a = window.location.hash.split('?')[1])
a.split(/&/g).forEach(function(item) {
url[(item = item.split('='))[0]] = item[1];
})
return url
}
200.过滤器指定字段
function filterArrBySex(data, name) {
if (!name) {
console.log(name)
return data;
} else {
return data.filter(function(ele, index, self) {
if (ele.name.includes(name)) {
return ele
}
})
}
}
201.根据身份证获取出生年月
/**
* 根据身份证获取出生年月
* @param idCard
*/
function getBirthdayFromIdCard(idCard) {
var birthday = "";
if (idCard != null && idCard != "") {
if (idCard.length == 15) {
birthday = "19" + idCard.substr(6, 6);
} else if (idCard.length == 18) {
birthday = idCard.substr(6, 8);
}
birthday = birthday.replace(/(.{4})(.{2})/, "$1-$2-");
}
return birthday;
}
202.根据身份证获取年龄
/**
* 根据身份证获取年龄
* @param UUserCard
*/
function IdCard(UUserCard) {
//获取年龄
var myDate = new Date();
var month = myDate.getMonth() + 1;
var day = myDate.getDate();
var age = myDate.getFullYear() - UUserCard.substring(6, 10) - 1;
if (UUserCard.substring(10, 12) < month || UUserCard.substring(10, 12) == month && UUserCard.substring(12, 14) <= day) {
age++;
}
return age
}
//vue购物车金额结算
window.onload = function() {
var vm = new Vue({
el: '#app',
data: {
items: [{
id: 1,
name: "苹果",
price: 10,
count: 1,
url: "http://www.jq22.com/img/cs/500x500-1.png"
},
{
id: 2,
name: "蝴蝶",
price: 8,
count: 5,
url: "http://www.jq22.com/img/cs/500x500-2.png"
},
{
id: 3,
name: "小狗",
price: 100,
count: 1,
url: "http://www.jq22.com/img/cs/500x500-3.png"
},
{
id: 4,
name: "鲜花",
price: 10,
count: 1,
url: "http://www.jq22.com/img/cs/500x500-4.png"
}
],
search: ""
},
methods: {
},
filters: { //过滤器
numFilter: function(data, n) { //data==item.price 当前过滤的数据 n==2
return "¥" + data.toFixed(n)
}
},
computed: { //计算属性
totalCount: function() {
var n = 0;
this.items.forEach((v, i) => {
n += v.count
});
return n;
},
totalPrice: function() {
var money = 0;
this.items.forEach((v, i) => {
money += v.count * v.price
});
return money;
},
searchFor: function() {
if (!this.search) {
return this.items
}
return this.items.filter((v, i) => {
if (v.name.indexOf(this.search) !== -1) { //匹配成功
return v
}
})
}
}
})
}
//设置iframe高度
function setIframeHeight(sonH) { //debugger;
var height = 0;
//比较父子页面高度,以高度更大的为准
var parentH = $(window).height(); //iframe最小高度应为浏览器视口高度,否则门户管理页面弹窗大小会受限制
height = parentH > sonH ? parentH : sonH;
$('#mainIframe').height(height);
//子页面有传值过来,覆盖iframe的最小高度-2000px
$("#mainIframe").css("min-height", 'auto');
$(".body-bg").css("height", height + 200);
try {
var childBody = $("#mainIframe")[0].contentWindow.document.getElementsByTagName("body")[0];
//childBody.style.minHeight = height + "px";
} catch (error) {
if (error.message.indexOf("Blocked from frame") > -1) console.warn("当前页面存在跨域!");
}
}
(function($) {
$("#username").keyup(function(event) {
if (event.keyCode == 13) $("#password").focus().select();
});
$("#password").keyup(function(event) {
if (event.keyCode == 13) $("#login-button").click();
});
})(jQuery);
//回到顶部
function goTop() {
window.scrollTo({
top: 0,
behavior: 'smooth',
});
}
window.onscroll = function() {
var t = document.documentElement.scrollTop;
if (t > 50) {
$(".toTop").fadeIn();
} else {
$(".toTop").fadeOut();
}
}
function urlAnalysis() {
var url = window.location.href;
var paraString = url.substring(url.indexOf("?") + 1, url.length);
var indexFirst = paraString.indexOf("&");
var paraStringTitle = paraString.slice(0, indexFirst);
paraStringElse = paraString.slice(indexFirst + 1, paraString.length);
var paraStringUrl = paraStringElse;
//区分是否传参:functionId
if (paraString.indexOf("functionId") > -1) {
var indexSecond = paraStringElse.indexOf("&");
var paraStringFId = paraStringElse.slice(0, indexSecond);
var functionId = paraStringFId.split("=")[1];
var $body = angular.element(document.body);
var $rootScope = $body.scope().$root;
$rootScope.navFunctionId = functionId;
paraStringUrl = paraStringElse.slice(indexSecond + 1, paraStringElse.length);
}
var title = paraStringTitle.split("=")[1] === "undefined" ? "" : decodeURI(paraStringTitle.split("=")[1]);
var indexUrl = paraStringUrl.indexOf("=");
var iframeUrl = paraStringUrl.slice(indexUrl + 1, paraStringUrl.length);
document.title = title;
$("#mainIframe").attr("src", iframeUrl);
}
// 监听enter按下事件,页面跳转
$scope.enterEvent = function(e) {
var keycode = window.event ? e.keyCode : e.which;
if (keycode == 13) {
console.log($scope.searchVal)
console.log('监听成功')
var baseUrl = '#/pages/knowlege/knowlegeSeach.html'
window.open(baseUrl)
}
};
function showDate() {
var myDate = new Date();
var year = myDate.getFullYear();
var month = myDate.getMonth() + 1;
month = month < 10 ? '0' + month : month;
var date = myDate.getDate();
date = date < 10 ? '0' + date : date;
var weekDay = myDate.getDay();
switch (weekDay) {
case 0:
weekDay = "天";
break;
case 1:
weekDay = "一";
break;
case 2:
weekDay = "二";
break;
case 3:
weekDay = "三";
break;
case 4:
weekDay = "四";
break;
case 5:
weekDay = "五";
break;
case 6:
weekDay = "六";
break;
"name"
}
$scope.year = year;
$scope.month = month;
$scope.date = date;
$scope.weekDay = weekDay;
}
//获取跳转的classId,通过hash方式获取
$scope.getQueryString = function() {
var obg = {},
a = '';
(a = window.location.search.substr(1)) || (a = window.location.hash.split('?')[1])
a.split(/&/g).forEach(function(item) {
obg[(item = item.split('='))[0]] = item[1];
})
return obg
}
var classId = $scope.getQueryString();
203.原生js滑块验证
//event.clientX:鼠标点下的点到左侧x轴的距离
window.onload = function() {
//事件处理 onmousedown onmousemove onmouseup
var box = document.querySelector(".box")
var btn = document.querySelector(".btn")
var bg = document.querySelector(".bg")
var text1 = document.querySelector(".text")
//封装的选择器 声明式函数可以提升
// function fun(){
//
// }
var flag = false; //标记
btn.onmousedown = function(event) {
var downx = event.clientX; //按下后获取的与x轴的距离
btn.onmousemove = function(e) {
var movex = e.clientX - downx; //滑块滑动的距离
//移动的范围
if (movex > 0) {
this.style.left = movex + "px";
bg.style.width = movex + "px";
if (movex >= box.offsetWidth - 40) {
//验证成功
flag = true
text1.innerHTML = "验证成功"
text1.style.color = "#fff"
//清除事件
btn.onmousedown = null;
btn.onmousemove = null;
}
}
}
}
//松开事件
btn.onmouseup = function() {
//清除事件
btn.onmousemove = null;
if (flag) return;
this.style.left = 0;
bg.style.width = 0 + "px";
}
}
204.纯 js无限加载瀑布(原创)
//随机[m,n]之间的整数 封装
function randomNumber(m, n) {
return Math.floor(Math.random() * (n - m + 1) + m);
}
//随机颜色 封装
function randomColor() {
return "rgb(" + randomNumber(0, 255) + "," + randomNumber(0, 255) + "," + randomNumber(0, 255) + ")";
}
//获取当前的scrollTop
var scrollTopDistance;
//获取所有的ul
var uls = document.querySelectorAll("ul");
var i = 0;
var k = i;
function waterFall() {
for (i = k; i < k + 4; i++) {
//创建li
var li = document.createElement("li");
//随机颜色
li.style.backgroundColor = randomColor();
//随机高度
li.style.height = randomNumber(120, 400) + "px";
//手动转换为字符串
li.innerHTML = i + 1 + "";
//插入到对应的ul中
//判断哪个ul的高度低,该次创建的li就插入到此ul中
var index = 0; //记录下标
for (var j = 0; j < uls.length; j++) {
if (uls[j].offsetHeight < uls[index].offsetHeight) {
index = j;
}
}
//将元素节点插入文档中
uls[index].appendChild(li);
}
k = i;
return uls[index].offsetHeight;
}
waterFall();
//鼠标滚轮事件,由于右侧没有滚轮,所以使用onmousewheel事件
window.onmousewheel = function() {
//获取窗口的高度,要兼容浏览器
var windowH = document.documentElement.clientHeight;
//滚轮于top的距离,要兼容浏览器
var scrollH = document.documentElement.scrollTop ||
document.body.scrollTop;
//获取窗口的可见高度
var documentH = document.documentElement.scrollHeight ||
document.body.scrollHeight;
//窗口的高度 + 滚轮与顶部的距离 > 窗口的可见高度-200
if (windowH + scrollH > documentH - 200) {
//执行此函数
waterFall()
}
}
205.jQuery两个元素比较高度
$(*function* () {
*var* w_max = 0;
*//求最大高度*
$("#MenuNavigation li").each(*function* () {
*var* w = $(*this*).innerWidth();
w_max = w > w_max ? w : w_max;
})
$("#MenuNavigation li").width(w_max)
*//将最大高度赋值给所有元素,*
})
206.js定时清除缓存,存储缓存,获取缓存
// 封装本地存储的方法
export const storage = {
set: function(variable, value, ttl_ms) {
var data = { value: value, expires_at: new Date(ttl_ms).getTime() };
localStorage.setItem(variable.toString(), JSON.stringify(data));
},
get: function(variable) {
var data = JSON.parse(localStorage.getItem(variable.toString()));
if (data !== null) {
debugger
if (data.expires_at !== null && data.expires_at < new Date().getTime()) {
localStorage.removeItem(variable.toString());
} else {
return data.value;
}
}
return null;
},
remove(key) {
localStorage.removeItem(key);
}
}
207.数组降维
//数组降维
reduceDimension(arr) {
var reduced = [];
for (var i = 0; i < arr.length; i++) {
reduced = reduced.concat(arr[i]);
}
return reduced;
}
208.设置cookie,获取cookie,删除cookie
var cookieUtil = {
getCookie: function (name) {
var arrCookie = document.cookie.split("; ");
for (var i = 0; i < arrCookie.length; i++) {
var cookieItem = arrCookie[i].split('=');
if (cookieItem[0] == name) {
return cookieItem[1];
}
}
return undefined;
},
setCookie: function (name, value, expires, path, domain, secure) {
var cookieText = encodeURIComponent(name) + "=" +
encodeURIComponent(value);
if (expires instanceof Date) {
cookieText += "; expires=" + expires.toGMTString();
}
if (path) {
cookieText += "; path=" + path;
}
if (domain) {
cookieText += "; domain=" + domain;
}
if (secure) {
cookieText += "; secure";
}
document.cookie = cookieText;
},
removeCookie: function (name, path, domain, secure) {
this.set(name, "", new Date(0), path, domain, secure);
}
}
209.判读是否为外链
/**
* @description 判读是否为外链
* @param path
* @returns {boolean}
*/
export function isExternal(path) {
return /^(https?:|mailto:|tel:)/.test(path);
}
210.校验密码是否小于6位
/**
* @description 校验密码是否小于6位
* @param str
* @returns {boolean}
*/
export function isPassword(str) {
return str.length >= 6;
}
211.判断是否为数字
/**
* @description 判断是否为数字
* @param value
* @returns {boolean}
*/
export function isNumber(value) {
const reg = /^[0-9]*$/;
return reg.test(value);
}
## 212.判断是否是名称
/**
* @description 判断是否是名称
* @param value
* @returns {boolean}
*/
export function isName(value) {
const reg = /^[\u4e00-\u9fa5a-zA-Z0-9]+$/;
return reg.test(value);
}
213.判断是否为IP
/**
* @description 判断是否为IP
* @param ip
* @returns {boolean}
*/
export function isIP(ip) {
const reg = /^(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])$/;
return reg.test(ip);
}
214.判断是否是传统网站
/**
* @description 判断是否是传统网站
* @param url
* @returns {boolean}
*/
export function isUrl(url) {
const reg = /^(https?|ftp):\/\/([a-zA-Z0-9.-]+(:[a-zA-Z0-9.&%$-]+)*@)*((25[0-5]|2[0-4][0-9]|1[0-9]{2}|[1-9][0-9]?)(\.(25[0-5]|2[0-4][0-9]|1[0-9]{2}|[1-9]?[0-9])){3}|([a-zA-Z0-9-]+\.)*[a-zA-Z0-9-]+\.(com|edu|gov|int|mil|net|org|biz|arpa|info|name|pro|aero|coop|museum|[a-zA-Z]{2}))(:[0-9]+)*(\/($|[a-zA-Z0-9.,?'\\+&%$#=~_-]+))*$/;
return reg.test(url);
}
215.判断是否是小写字母
/**
* @description 判断是否是小写字母
* @param str
* @returns {boolean}
*/
export function isLowerCase(str) {
const reg = /^[a-z]+$/;
return reg.test(str);
}
216.判断是否是大写字母
/**
* @description 判断是否是大写字母
* @param str
* @returns {boolean}
*/
export function isUpperCase(str) {
const reg = /^[A-Z]+$/;
return reg.test(str);
}
217.判断是否是大写字母开头
/**
* @description 判断是否是大写字母开头
* @param str
* @returns {boolean}
*/
export function isAlphabets(str) {
const reg = /^[A-Za-z]+$/;
return reg.test(str);
}
218.判断是否是字符串
/**
* @description 判断是否是字符串
* @param str
* @returns {boolean}
*/
export function isString(str) {
return typeof str === "string" || str instanceof String;
}
219.判断是否是数组
/**
* @description 判断是否是数组
* @param arg
* @returns {arg is any[]|boolean}
*/
export function isArray(arg) {
if (typeof Array.isArray === "undefined") {
return Object.prototype.toString.call(arg) === "[object Array]";
}
return Array.isArray(arg);
}
220.判断是否是端口号
/**
* @description 判断是否是端口号
* @param str
* @returns {boolean}
*/
export function isPort(str) {
const reg = /^([0-9]|[1-9]\d|[1-9]\d{2}|[1-9]\d{3}|[1-5]\d{4}|6[0-4]\d{3}|65[0-4]\d{2}|655[0-2]\d|6553[0-5])$/;
return reg.test(str);
}
221.判断是否是手机号
/**
* @description 判断是否是手机号
* @param str
* @returns {boolean}
*/
export function isPhone(str) {
const reg = /^1\d{10}$/;
return reg.test(str);
}
222.判断是否是身份证号(第二代)
/**
* @description 判断是否是身份证号(第二代)
* @param str
* @returns {boolean}
*/
export function isIdCard(str) {
const reg = /^[1-9]\d{5}(18|19|([23]\d))\d{2}((0[1-9])|(10|11|12))(([0-2][1-9])|10|20|30|31)\d{3}[0-9Xx]$/;
return reg.test(str);
}
223.判断是否是邮箱
/**
* @description 判断是否是邮箱
* @param str
* @returns {boolean}
*/
export function isEmail(str) {
const reg = /^\w+([-+.]\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*$/;
return reg.test(str);
}
## 224.判断是否中文
/**
* @description 判断是否中文
* @param str
* @returns {boolean}
*/
export function isChina(str) {
const reg = /^[\u4E00-\u9FA5]{2,4}$/;
return reg.test(str);
}
## 225.判断是否为空
/**
* @description 判断是否为空
* @param str
* @returns {boolean}
*/
export function isBlank(str) {
return (
str == null ||
false ||
str === "" ||
str.trim() === "" ||
str.toLocaleLowerCase().trim() === "null"
);
}
## 226.判断是否为固话
/**
* @description 判断是否为固话
* @param str
* @returns {boolean}
*/
export function isTel(str) {
const reg = /^(400|800)([0-9\\-]{7,10})|(([0-9]{4}|[0-9]{3})(-| )?)?([0-9]{7,8})((-| |转)*([0-9]{1,4}))?$/;
return reg.test(str);
}
## 227.判断是否为数字且最多两位小数
/**
* @description 判断是否为数字且最多两位小数
* @param str
* @returns {boolean}
*/
export function isNum(str) {
const reg = /^\d+(\.\d{1,2})?$/;
return reg.test(str);
}
## 228.判断经度 -180.0~+180.0(整数部分为0~180,必须输入1到5位小数)
/**
* @description 判断经度 -180.0~+180.0(整数部分为0~180,必须输入1到5位小数)
* @param str
* @returns {boolean}
*/
export function isLongitude(str) {
const reg = /^[-|+]?(0?\d{1,2}\.\d{1,5}|1[0-7]?\d{1}\.\d{1,5}|180\.0{1,5})$/;
return reg.test(str);
}
## 229.判断纬度 -90.0~+90.0(整数部分为0~90,必须输入1到5位小数)
/**
* @description 判断纬度 -90.0~+90.0(整数部分为0~90,必须输入1到5位小数)
* @param str
* @returns {boolean}
*/
export function isLatitude(str) {
const reg = /^[-|+]?([0-8]?\d{1}\.\d{1,5}|90\.0{1,5})$/;
return reg.test(str);
}
## 230.rtsp校验只要有rtsp://
/**
* @description rtsp校验,只要有rtsp://
* @param str
* @returns {boolean}
*/
export function isRTSP(str) {
const reg = /^rtsp:\/\/([a-z]{0,10}:.{0,10}@)?(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])$/;
const reg1 = /^rtsp:\/\/([a-z]{0,10}:.{0,10}@)?(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5]):[0-9]{1,5}/;
const reg2 = /^rtsp:\/\/([a-z]{0,10}:.{0,10}@)?(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\//;
return reg.test(str) || reg1.test(str) || reg2.test(str);
}
231.判断IE浏览器版本和检测是否为非IE浏览器
function IEVersion() {
var userAgent = navigator.userAgent; //取得浏览器的userAgent字符串
var isIE = userAgent.indexOf("compatible") > -1 && userAgent.indexOf("MSIE") > -1; //判断是否IE<11浏览器
var isEdge = userAgent.indexOf("Edge") > -1 && !isIE; //判断是否IE的Edge浏览器
var isIE11 = userAgent.indexOf('Trident') > -1 && userAgent.indexOf("rv:11.0") > -1;
if (isIE) {
var reIE = new RegExp("MSIE (\\d+\\.\\d+);");
reIE.test(userAgent);
var fIEVersion = parseFloat(RegExp["$1"]);
if (fIEVersion == 7) {
return 7;
} else if (fIEVersion == 8) {
return 8;
} else if (fIEVersion == 9) {
return 9;
} else if (fIEVersion == 10) {
return 10;
} else {
return 6; //IE版本<=7
}
} else if (isEdge) {
return 'edge'; //edge
} else if (isIE11) {
return 11; //IE11
} else {
return -1; //不是ie浏览器
}
}
232.数组去重
方案一:Set + …
function noRepeat(arr) {
return [...new Set(arr)];
}
noRepeat([1,2,3,1,2,3])
方案二:Set + Array.from
function noRepeat(arr) {
return Array.from(new Set(arr));
}
noRepeat([1,2,3,1,2,3])
方案三:双重遍历比对下标
function noRepeat(arr) {
return arr.filter((v, idx)=>idx == arr.lastIndexOf(v))
}
noRepeat([1,2,3,1,2,3])
方案四:单遍历 + Object 特性
Object 的特性是 Key 不会重复。 这里使用 values 是因为可以保留类型,keys 会变成字符串。
function noRepeat(arr) {
return Object.values(arr.reduce((s,n)=>{
s[n] = n;
return s
},{}))
}
noRepeat([1,2,3,1,2,3])
后记
针对于上述的方案,还有其他变种实现。
233.查找数组最大
方案一:Math.max + …
function arrayMax(arr) {
return Math.max(...arr);
}
arrayMax([-1,-4,5,2,0])
方案二:Math.max + apply
function arrayMax(arr) {
return Math.max.apply(Math, arr)
}
arrayMax([-1,-4,5,2,0])
方案三:Math.max
+ 遍历
function arrayMax(arr) {
return arr.reduce((s,n)=>Math.max(s, n))
}
arrayMax([-1,-4,5,2,0])
方案四:比较、条件运算法 + 遍历
function arrayMax(arr) {
return arr.reduce((s,n)=>s>n?s:n)
}
arrayMax([-1,-4,5,2,0])
方案五:排序
function arrayMax(arr) {
return arr.sort((n,m)=>m-n)[0]
}
arrayMax([-1,-4,5,2,0])
234.查找数组最小
同上,不明白为什么要分成两个题目。
Math.max
换成Math.min
s>n?s:n
换成s
(n,m)=>m-n换成
(n,m)=>n-m,或者直接取最后一个元素</ol>¨K273K¨K274K¨G108G¨K275K¨G109G¨K276K¨G110G¨K277K¨K278K¨G111G¨K279K¨G112G¨K280K¨K281K¨G113G¨K282K¨G114G¨K283K¨K284K他原文有问题,以下方法的
4,5没有返回¨G115G需要再操作一遍¨G116G¨K285K算是方案1的变种吧,优化了
includes` 的性能。
237.返回两个数组中相同的元素
方案一:filter + includes
function intersection(arr1, arr2) {
return arr2.filter((v) => arr1.includes(v));
}
intersection([1,2,3], [3,4,5,2])
方案二:同理变种用 hash
function intersection(arr1, arr2) {
var set = new Set(arr2)
return arr1.filter((v) => set.has(v));
}
intersection([1,2,3], [3,4,5,2])
238.从右删除 n 个元素
方案一:slice
function dropRight(arr, n = 0) {
return n < arr.length ? arr.slice(0, arr.length - n) : [];
}
dropRight([1,2,3,4,5], 2)
方案二: splice
function dropRight(arr, n = 0) {
return arr.splice(0, arr.length - n)
}
dropRight([1,2,3,4,5], 2)
方案三: slice 另一种
function dropRight(arr, n = 0) {
return arr.slice(0, -n)
}
dropRight([1,2,3,4,5], 2)
方案四: 修改 length
function dropRight(arr, n = 0) {
arr.length = Math.max(arr.length - n, 0)
return arr
}
dropRight([1,2,3,4,5], 2)
239.截取第一个符合条件的元素及其以后的元素
方案一:slice + 循环
function dropElements(arr, fn) {
while (arr.length && !fn(arr[0])) arr = arr.slice(1);
return arr;
}
dropElements([1,2,3,4,5,1,2,3], (v) => v == 2)
方案二:findIndex + slice
function dropElements(arr, fn) {
return arr.slice(Math.max(arr.findIndex(fn), 0));
}
dropElements([1,2,3,4,5,1,2,3], (v) => v === 3)
方案三:splice + 循环
function dropElements(arr, fn) {
while (arr.length && !fn(arr[0])) arr.splice(0,1);
return arr;
}
dropElements([1,2,3,4,5,1,2,3], (v) => v == 2)
240.返回数组中下标间隔 nth 的元素
方案一:filter
function everyNth(arr, nth) {
return arr.filter((v, i) => i % nth === nth - 1);
}
everyNth([1,2,3,4,5,6,7,8], 2)
方案二:方案一修改判断条件
function everyNth(arr, nth) {
return arr.filter((v, i) => (i+1) % nth === 0);
}
everyNth([1,2,3,4,5,6,7,8], 2)
241.返回数组中第 n 个元素(支持负数)
方案一:slice
function nthElement(arr, n = 0) {
return (n >= 0 ? arr.slice(n, n + 1) : arr.slice(n))[0];
}
nthElement([1,2,3,4,5], 0)
nthElement([1,2,3,4,5], -1)
方案二:三目运算符
function nthElement(arr, n = 0) {
return (n >= 0 ? arr[0] : arr[arr.length + n])
}
nthElement([1,2,3,4,5], 0)
nthElement([1,2,3,4,5], -1)
242.返回数组头元素
方案一:
function head(arr) {
return arr[0];
}
head([1,2,3,4])
方案二:
function head(arr) {
return arr.slice(0,1)[0];
}
head([1,2,3,4])
243.返回数组末尾元素
方案一:
function last(arr) {
return arr[arr.length - 1];
}
方案二:
function last(arr) {
return arr.slice(-1)[0];
}
last([1,2,3,4,5])
245.数组乱排
方案一:洗牌算法
function shuffle(arr) {
let array = arr;
let index = array.length;
while (index) {
index -= 1;
let randomInedx = Math.floor(Math.random() * index);
let middleware = array[index];
array[index] = array[randomInedx];
array[randomInedx] = middleware;
}
return array;
}
shuffle([1,2,3,4,5])
方案二:sort + random
function shuffle(arr) {
return arr.sort((n,m)=>Math.random() - .5)
}
shuffle([1,2,3,4,5])
246.伪数组转换为数组
方案一:Array.from
Array.from({length: 2})
方案二:prototype.slice
Array.prototype.slice.call({length: 2,1:1})
方案三:prototype.splice
Array.prototype.splice.call({length: 2,1:1},0)
浏览器对象 BOM
195.判读浏览器是否支持 CSS 属性
/**
* 告知浏览器支持的指定css属性情况
* @param {String} key - css属性,是属性的名字,不需要加前缀
* @returns {String} - 支持的属性情况
*/
function validateCssKey(key) {
const jsKey = toCamelCase(key); // 有些css属性是连字符号形成
if (jsKey in document.documentElement.style) {
return key;
}
let validKey = "";
// 属性名为前缀在js中的形式,属性值是前缀在css中的形式
// 经尝试,Webkit 也可是首字母小写 webkit
const prefixMap = {
Webkit: "-webkit-",
Moz: "-moz-",
ms: "-ms-",
O: "-o-",
};
for (const jsPrefix in prefixMap) {
const styleKey = toCamelCase(`${jsPrefix}-${jsKey}`);
if (styleKey in document.documentElement.style) {
validKey = prefixMap[jsPrefix] + key;
break;
}
}
return validKey;
}
/**
* 把有连字符号的字符串转化为驼峰命名法的字符串
*/
function toCamelCase(value) {
return value.replace(/-(\w)/g, (matched, letter) => {
return letter.toUpperCase();
});
}
/**
* 检查浏览器是否支持某个css属性值(es6版)
* @param {String} key - 检查的属性值所属的css属性名
* @param {String} value - 要检查的css属性值(不要带前缀)
* @returns {String} - 返回浏览器支持的属性值
*/
function valiateCssValue(key, value) {
const prefix = ["-o-", "-ms-", "-moz-", "-webkit-", ""];
const prefixValue = prefix.map((item) => {
return item + value;
});
const element = document.createElement("div");
const eleStyle = element.style;
// 应用每个前缀的情况,且最后也要应用上没有前缀的情况,看最后浏览器起效的何种情况
// 这就是最好在prefix里的最后一个元素是''
prefixValue.forEach((item) => {
eleStyle[key] = item;
});
return eleStyle[key];
}
/**
* 检查浏览器是否支持某个css属性值
* @param {String} key - 检查的属性值所属的css属性名
* @param {String} value - 要检查的css属性值(不要带前缀)
* @returns {String} - 返回浏览器支持的属性值
*/
function valiateCssValue(key, value) {
var prefix = ["-o-", "-ms-", "-moz-", "-webkit-", ""];
var prefixValue = [];
for (var i = 0; i < prefix.length; i++) {
prefixValue.push(prefix[i] + value);
}
var element = document.createElement("div");
var eleStyle = element.style;
for (var j = 0; j < prefixValue.length; j++) {
eleStyle[key] = prefixValue[j];
}
return eleStyle[key];
}
function validCss(key, value) {
const validCss = validateCssKey(key);
if (validCss) {
return validCss;
}
return valiateCssValue(key, value);
}
https://segmentfault.com/a/11… 它里面有 forEach。
247.返回当前网页地址
方案一:location
function currentURL() {
return window.location.href;
}
currentURL()
方案二:a 标签
function currentURL() {
var el = document.createElement('a')
el.href = ''
return el.href
}
currentURL()
获取滚动条位置
function getScrollPosition(el = window) {
return {
x: el.pageXOffset !== undefined ? el.pageXOffset : el.scrollLeft,
y: el.pageYOffset !== undefined ? el.pageYOffset : el.scrollTop,
};
}
248.获取 url 中的参数
方案一:正则 + reduce
function getURLParameters(url) {
return url
.match(/([^?=&]+)(=([^&]*))/g)
.reduce(
(a, v) => (
(a[v.slice(0, v.indexOf("="))] = v.slice(v.indexOf("=") + 1)), a
),
{}
);
}
getURLParameters(location.href)
方案二:split + reduce
function getURLParameters(url) {
return url
.split('?') //取?分割
.slice(1) //不要第一部分
.join() //拼接
.split('&')//&分割
.map(v=>v.split('=')) //=分割
.reduce((s,n)=>{s[n[0]] = n[1];return s},{})
}
getURLParameters(location.href)
// getURLParameters('')
方案三: URLSearchParams
249.页面跳转,是否记录在 history 中
方案一:
function redirect(url, asLink = true) {
asLink ? (window.location.href = url) : window.location.replace(url);
}
方案二:
function redirect(url, asLink = true) {
asLink ? window.location.assign(url) : window.location.replace(url);
}
250.滚动条回到顶部动画
方案一: c – c / 8
c 没有定义
function scrollToTop() {
const scrollTop =
document.documentElement.scrollTop || document.body.scrollTop;
if (scrollTop > 0) {
window.requestAnimationFrame(scrollToTop);
window.scrollTo(0, c - c / 8);
} else {
window.cancelAnimationFrame(scrollToTop);
}
}
scrollToTop()
修正之后
function scrollToTop() {
const scrollTop =
document.documentElement.scrollTop || document.body.scrollTop;
if (scrollTop > 0) {
window.requestAnimationFrame(scrollToTop);
window.scrollTo(0, scrollTop - scrollTop / 8);
} else {
window.cancelAnimationFrame(scrollToTop);
}
}
scrollToTop()
251.复制文本
方案一:
function copy(str) {
const el = document.createElement("textarea");
el.value = str;
el.setAttribute("readonly", "");
el.style.position = "absolute";
el.style.left = "-9999px";
el.style.top = "-9999px";
document.body.appendChild(el);
const selected =
document.getSelection().rangeCount > 0
? document.getSelection().getRangeAt(0)
: false;
el.select();
document.execCommand("copy");
document.body.removeChild(el);
if (selected) {
document.getSelection().removeAllRanges();
document.getSelection().addRange(selected);
}
}
方案二:cliboard.js
252.检测设备类型
方案一: ua
function detectDeviceType() {
return /Android|webOS|iPhone|iPad|iPod|BlackBerry|IEMobile|Opera Mini/i.test(
navigator.userAgent
)
? "Mobile"
: "Desktop";
}
detectDeviceType()
方案二:事件属性
function detectDeviceType() {
return ("ontouchstart" in window || navigator.msMaxTouchPoints)
? "Mobile"
: "Desktop";
}
detectDeviceType()
253.Cookie
增
function setCookie(key, value, expiredays) {
var exdate = new Date();
exdate.setDate(exdate.getDate() + expiredays);
document.cookie =
key +
"=" +
escape(value) +
(expiredays == null ? "" : ";expires=" + exdate.toGMTString());
}
删
function delCookie(name) {
var exp = new Date();
exp.setTime(exp.getTime() - 1);
var cval = getCookie(name);
if (cval != null) {
document.cookie = name + "=" + cval + ";expires=" + exp.toGMTString();
}
}
查
function getCookie(name) {
var arr,
reg = new RegExp("(^| )" + name + "=([^;]*)(;|$)");
if ((arr = document.cookie.match(reg))) {
return arr[2];
} else {
return null;
}
}
清空
有时候我们想清空,但是又无法获取到所有的cookie。 这个时候我们可以了利用写满,然后再清空的办法。
日期 Date
254.时间戳转换为时间
function timestampToTime(timestamp = Date.parse(new Date()), isMs = true) {
const date = new Date(timestamp * (isMs ? 1 : 1000));
return `${date.getFullYear()}-${
date.getMonth() + 1 < 10 ? "0" + (date.getMonth() + 1) : date.getMonth() + 1
}-${date.getDate()} ${date.getHours()}:${date.getMinutes()}:${date.getSeconds()}`;
}
如果做海外的话,还会有时区问题,一般我用moment解决。如果想看原生的
获取当前时间戳
基于上一个想到的问题
方案一:Date.parse(new Date())
方案二:Date.now()
方案三:+new Date()
文档对象 DOM
255固定滚动条
/**
* 功能描述:一些业务场景,如弹框出现时,需要禁止页面滚动,这是兼容安卓和 iOS 禁止页面滚动的解决方案
*/
let scrollTop = 0;
function preventScroll() {
// 存储当前滚动位置
scrollTop = window.scrollY;
// 将可滚动区域固定定位,可滚动区域高度为 0 后就不能滚动了
document.body.style["overflow-y"] = "hidden";
document.body.style.position = "fixed";
document.body.style.width = "100%";
document.body.style.top = -scrollTop + "px";
// document.body.style['overscroll-behavior'] = 'none'
}
function recoverScroll() {
document.body.style["overflow-y"] = "auto";
document.body.style.position = "static";
// document.querySelector('body').style['overscroll-behavior'] = 'none'
window.scrollTo(0, scrollTop);
}
256 判断当前位置是否为页面底部
function bottomVisible() {
return (
document.documentElement.clientHeight + window.scrollY >=
(document.documentElement.scrollHeight ||
document.documentElement.clientHeight)
);
}
257判断元素是否在可视范围内
function elementIsVisibleInViewport(el, partiallyVisible = false) {
const { top, left, bottom, right } = el.getBoundingClientRect();
return partiallyVisible
? ((top > 0 && top < innerHeight) ||
(bottom > 0 && bottom < innerHeight)) &&
((left > 0 && left < innerWidth) || (right > 0 && right < innerWidth))
: top >= 0 && left >= 0 && bottom <= innerHeight && right <= innerWidth;
}
258.获取元素 css 样式
function getStyle(el, ruleName) {
return getComputedStyle(el, null).getPropertyValue(ruleName);
}
259.进入全屏
function launchFullscreen(element) {
if (element.requestFullscreen) {
element.requestFullscreen();
} else if (element.mozRequestFullScreen) {
element.mozRequestFullScreen();
} else if (element.msRequestFullscreen) {
element.msRequestFullscreen();
} else if (element.webkitRequestFullscreen) {
element.webkitRequestFullScreen();
}
}
launchFullscreen(document.documentElement);
launchFullscreen(document.getElementById("id")); //某个元素进入全屏
260退出全屏
function exitFullscreen() {
if (document.exitFullscreen) {
document.exitFullscreen();
} else if (document.msExitFullscreen) {
document.msExitFullscreen();
} else if (document.mozCancelFullScreen) {
document.mozCancelFullScreen();
} else if (document.webkitExitFullscreen) {
document.webkitExitFullscreen();
}
}
exitFullscreen();
261全屏事件
document.addEventListener("fullscreenchange", function (e) {
if (document.fullscreenElement) {
console.log("进入全屏");
} else {
console.log("退出全屏");
}
});
数字 Number
262.数字千分位分割
function commafy(num) {
return num.toString().indexOf(".") !== -1
? num.toLocaleString()
: num.toString().replace(/(\d)(?=(?:\d{3})+$)/g, "$1,");
}
commafy(1000)
263.生成随机数
function randomNum(min, max) {
switch (arguments.length) {
case 1:
return parseInt(Math.random() * min + 1, 10);
case 2:
return parseInt(Math.random() * (max - min + 1) + min, 10);
default:
return 0;
}
}
randomNum(1,10)
264 时间戳转时间
/* 时间戳转时间 */
function timestampToTime(cjsj) {
var date = new Date(cjsj); //时间戳为10位需*1000,时间戳为13位的话不需乘1000
var Y = date.getFullYear() + '-';
var M = (date.getMonth() + 1 < 10 ? '0' + (date.getMonth() + 1) : date.getMonth() + 1) + '-';
var D = (date.getDate() + 1 < 10 ? '0' + (date.getDate()) : date.getDate()) + ' ';
return Y + M + D
}
265 过滤富文本和空格为纯文本
/* 过滤富文本和空格为纯文本 */
function filterHtml(str) {
return str.replace(/<[^<>]+>/g, '').replace(/ /ig, '');
}
266 指定显示的文字数量多余的使用省略号代替
/*指定显示的文字数量多余的使用省略号代替*/
function strEllp(str, num = str.length) {
var subStr = str.substring(0, num);
return subStr + (str.length > num ? '...' : '');
}
267 获取滚动条当前的位置
// 获取滚动条当前的位置
function getScrollTop() {
var scrollTop = 0
if (document.documentElement && document.documentElement.scrollTop) {
scrollTop = document.documentElement.scrollTop;
} else if (document.body) {
scrollTop = document.body.scrollTop;
}
return scrollTop
}
268 获取当前可视范围的高度
// 获取当前可视范围的高度
function getClientHeight() {
var clientHeight = 0
if (document.body.clientHeight && document.documentElement.clientHeight) {
clientHeight = Math.min(document.body.clientHeight, document.documentElement.clientHeight)
} else {
clientHeight = Math.max(document.body.clientHeight, document.documentElement.clientHeight)
}
return clientHeight
}
269 获取文档完整的高度
// 获取文档完整的高度
function getScrollHeight() {
return Math.max(document.body.scrollHeight, document.documentElement.scrollHeight)
}
- partiallyVisible 为是否为完全可见
- 返回值为 true/false
- 默认为当前时间转换结果
- isMs 为时间戳是否为毫秒
a. 补位可以改成 padStart
b. 补位还可以改成 slice