1、输入一个值，返回其数据类型**
function type(para) {
return Object.prototype.toString.call(para)
}
2、数组去重
function unique1(arr) {
return [...new Set(arr)]
}
function unique2(arr) {
var obj = {};
return arr.filter(ele => {
if (!obj[ele]) {
obj[ele] = true;
return true;
}
})
}
function unique3(arr) {
var result = [];
arr.forEach(ele => {
if (result.indexOf(ele) == -1) {
result.push(ele)
}
})
return result;
}
3、字符串去重
String.prototype.unique = function () {
var obj = {},
str = '',
len = this.length;
for (var i = 0; i < len; i++) {
if (!obj[this[i]]) {
str += this[i];
obj[this[i]] = true;
}
}
return str;
}
//去除连续的字符串
function uniq(str) {
return str.replace(/(\w)\1+/g, '$1')
}
去除字符串空格
const trim = function(str, type) { // 去除空格， type: 1-所有空格 2-前后空格 3-前空格 4-后空格
type = type || 1
switch (type) {
case 1:
return str.replace(/\s+/g, '')
case 2:
return str.replace(/(^\s*)|(\s*$)/g, '')
case 3:
return str.replace(/(^\s*)/g, '')
case 4:
return str.replace(/(\s*$)/g, '')
default:
return str
}
}
4、深拷贝 浅拷贝
//深克隆（深克隆不考虑函数）
function deepClone(obj, result) {
var result = result || {};
for (var prop in obj) {
if (obj.hasOwnProperty(prop)) {
if (typeof obj[prop] == 'object' && obj[prop] !== null) {
// 引用值(obj/array)且不为null
if (Object.prototype.toString.call(obj[prop]) == '[object Object]') {
// 对象
result[prop] = {};
} else {
// 数组
result[prop] = [];
}
deepClone(obj[prop], result[prop])
} else {
// 原始值或func
result[prop] = obj[prop]
}
}
}
return result;
}
// 深浅克隆是针对引用值
function deepClone(target) {
if (typeof (target) !== 'object') {
return target;
}
var result;
if (Object.prototype.toString.call(target) == '[object Array]') {
// 数组
result = []
} else {
// 对象
result = {};
}
for (var prop in target) {
if (target.hasOwnProperty(prop)) {
result[prop] = deepClone(target[prop])
}
}
return result;
}
// 无法复制函数
var o1 = jsON.parse(jsON.stringify(obj1));
5、reverse底层原理和扩展
// 改变原数组
Array.prototype.myReverse = function () {
var len = this.length;
for (var i = 0; i < len; i++) {
var temp = this[i];
this[i] = this[len - 1 - i];
this[len - 1 - i] = temp;
}
return this;
}
6、圣杯模式的继承
function inherit(Target, Origin) {
function F() {};
F.prototype = Origin.prototype;
Target.prototype = new F();
Target.prototype.constructor = Target;
// 最终的原型指向
Target.prop.uber = Origin.prototype;
}
7、找出字符串中第一次只出现一次的字母
String.prototype.firstAppear = function () {
var obj = {},
len = this.length;
for (var i = 0; i < len; i++) {
if (obj[this[i]]) {
obj[this[i]]++;
} else {
obj[this[i]] = 1;
}
}
for (var prop in obj) {
if (obj[prop] == 1) {
return prop;
}
}
}
8、找元素的第n级父元素
function parents(ele, n) {
while (ele && n) {
ele = ele.parentElement ? ele.parentElement : ele.parentNode;
n--;
}
return ele;
}
9、 返回元素的第n个兄弟节点
function retSibling(e, n) {
while (e && n) {
if (n > 0) {
if (e.nextElementSibling) {
e = e.nextElementSibling;
} else {
for (e = e.nextSibling; e && e.nodeType !== 1; e = e.nextSibling);
}
n--;
} else {
if (e.previousElementSibling) {
e = e.previousElementSibling;
} else {
for (e = e.previousElementSibling; e && e.nodeType !== 1; e = e.previousElementSibling);
}
n++;
}
}
return e;
}
10、封装mychildren，解决浏览器的兼容问题
function myChildren(e) {
var children = e.childNodes,
arr = [],
len = children.length;
for (var i = 0; i < len; i++) {
if (children[i].nodeType === 1) {
arr.push(children[i])
}
}
return arr;
}
11、判断元素有没有子元素
function hasChildren(e) {
var children = e.childNodes,
len = children.length;
for (var i = 0; i < len; i++) {
if (children[i].nodeType === 1) {
return true;
}
}
return false;
}
12、我一个元素插入到另一个元素的后面
Element.prototype.insertAfter = function (target, elen) {
var nextElen = elen.nextElenmentSibling;
if (nextElen == null) {
this.appendChild(target);
} else {
this.insertBefore(target, nextElen);
}
}
13、返回当前的时间（年月日时分秒）
function getDateTime() {
var date = new Date(),
year = date.getFullYear(),
month = date.getMonth() + 1,
day = date.getDate(),
hour = date.getHours() + 1,
minute = date.getMinutes(),
second = date.getSeconds();
month = checkTime(month);
day = checkTime(day);
hour = checkTime(hour);
minute = checkTime(minute);
second = checkTime(second);
function checkTime(i) {
if (i < 10) {
i = "0" + i;
}
return i;
}
return "" + year + "年" + month + "月" + day + "日" + hour + "时" + minute + "分" + second + "秒"
}
14、获得滚动条的滚动距离
function getScrollOffset() {
if (window.pageXOffset) {
return {
x: window.pageXOffset,
y: window.pageYOffset
}
} else {
return {
x: document.body.scrollLeft + document.documentElement.scrollLeft,
y: document.body.scrollTop + document.documentElement.scrollTop
}
}
}
- 浏览器操作
（1）滚动到页面顶部
export const scrollToTop = () => {
const height = document.documentElement.scrollTop || document.body.scrollTop;
if (height > 0) {
window.requestAnimationFrame(scrollToTop);
window.scrollTo(0, height - height / 8);
}
}
滚动到顶部
将元素滚动到顶部最简单的方法是使用scrollIntoView。设置block为start可以滚动到顶部；设置behavior为smooth可以开启平滑滚动。
const scrollToTop = (element) =>
element.scrollIntoView({ behavior: "smooth", block: "start" });
（2）滚动到页面底部
export const scrollToBottom = () => {
window.scrollTo(0, document.documentElement.clientHeight);
}
滚动到底部
与滚动到顶部一样，滚动到底部只需要设置block为end即可。
const scrollToBottom = (element) =>
element.scrollIntoView({ behavior: "smooth", block: "end" });
（3）滚动到指定元素区域
export const smoothScroll = (element) => {
document.querySelector(element).scrollIntoView({
behavior: 'smooth'
});
};
（4）获取可视窗口高度
export const getClientHeight = () => {
let clientHeight = 0;
if (document.body.clientHeight && document.documentElement.clientHeight) {
clientHeight = (document.body.clientHeight < document.documentElement.clientHeight) ? document.body.clientHeight : document.documentElement.clientHeight;
}
else {
clientHeight = (document.body.clientHeight > document.documentElement.clientHeight) ? document.body.clientHeight : document.documentElement.clientHeight;
}
return clientHeight;
}
（5）获取可视窗口宽度
export const getPageViewWidth = () => {
return (document.compatMode == "BackCompat" ? document.body : document.documentElement).clientWidth;
}
（6）打开浏览器全屏
export const toFullScreen = () => {
let element = document.body;
if (element.requestFullscreen) {
element.requestFullscreen()
} else if (element.mozRequestFullScreen) {
element.mozRequestFullScreen()
} else if (element.msRequestFullscreen) {
element.msRequestFullscreen()
} else if (element.webkitRequestFullscreen) {
element.webkitRequestFullScreen()
}
}
（7）退出浏览器全屏
export const exitFullscreen = () => {
if (document.exitFullscreen) {
document.exitFullscreen()
} else if (document.msExitFullscreen) {
document.msExitFullscreen()
} else if (document.mozCancelFullScreen) {
document.mozCancelFullScreen()
} else if (document.webkitExitFullscreen) {
document.webkitExitFullscreen()
}
}
15、获得视口的尺寸
function getViewportOffset() {
if (window.innerWidth) {
return {
w: window.innerWidth,
h: window.innerHeight
}
} else {
// ie8及其以下
if (document.compatMode === "BackCompat") {
// 怪异模式
return {
w: document.body.clientWidth,
h: document.body.clientHeight
}
} else {
// 标准模式
return {
w: document.documentElement.clientWidth,
h: document.documentElement.clientHeight
}
}
}
}
16、获取任一元素的任意属性
function getStyle(elem, prop) {
return window.getComputedStyle ? window.getComputedStyle(elem, null)[prop] : elem.currentStyle[prop]
}
17、绑定事件的兼容代码
function addEvent(elem, type, handle) {
if (elem.addEventListener) { //非ie和非ie9
elem.addEventListener(type, handle, false);
} else if (elem.attachEvent) { //ie6到ie8
elem.attachEvent('on' + type, function () {
handle.call(elem);
})
} else {
elem['on' + type] = handle;
}
}
18、解绑事件
function removeEvent(elem, type, handle) {
if (elem.removeEventListener) { //非ie和非ie9
elem.removeEventListener(type, handle, false);
} else if (elem.detachEvent) { //ie6到ie8
elem.detachEvent('on' + type, handle);
} else {
elem['on' + type] = null;
}
}
19、取消冒泡的兼容代码
function stopBubble(e) {
if (e && e.stopPropagation) {
e.stopPropagation();
} else {
window.event.cancelBubble = true;
}
}
20、检验字符串是否是回文
function isPalina(str) {
if (Object.prototype.toString.call(str) !== '[object String]') {
return false;
}
var len = str.length;
for (var i = 0; i < len / 2; i++) {
if (str[i] != str[len - 1 - i]) {
return false;
}
}
return true;
}
21、检验字符串是否是回文
function isPalindrome(str) {
str = str.replace(/\W/g, '').toLowerCase();
console.log(str)
return (str == str.split('').reverse().join(''))
}
22、兼容getElementsByClassName方法
Element.prototype.getElementsByClassName = Document.prototype.getElementsByClassName = function (_className) {
var allDomArray = document.getElementsByTagName('*');
var lastDomArray = [];
function trimSpace(strClass) {
var reg = /\s+/g;
return strClass.replace(reg, ' ').trim()
}
for (var i = 0; i < allDomArray.length; i++) {
var classArray = trimSpace(allDomArray[i].className).split(' ');
for (var j = 0; j < classArray.length; j++) {
if (classArray[j] == _className) {
lastDomArray.push(allDomArray[i]);
break;
}
}
}
return lastDomArray;
}
23、运动函数'
function animate(obj, json, callback) {
clearInterval(obj.timer);
var speed,
current;
obj.timer = setInterval(function () {
var lock = true;
for (var prop in json) {
if (prop == 'opacity') {
current = parseFloat(window.getComputedStyle(obj, null)[prop]) * 100;
} else {
current = parseInt(window.getComputedStyle(obj, null)[prop]);
}
speed = (json[prop] - current) / 7;
speed = speed > 0 ? Math.ceil(speed) : Math.floor(speed);
if (prop == 'opacity') {
obj.style[prop] = (current + speed) / 100;
} else {
obj.style[prop] = current + speed + 'px';
}
if (current != json[prop]) {
lock = false;
}
}
if (lock) {
clearInterval(obj.timer);
typeof callback == 'function' ? callback() : '';
}
}, 30)
}
24、弹性运动
function ElasticMovement(obj, target) {
clearInterval(obj.timer);
var iSpeed = 40,
a, u = 0.8;
obj.timer = setInterval(function () {
a = (target - obj.offsetLeft) / 8;
iSpeed = iSpeed + a;
iSpeed = iSpeed * u;
if (Math.abs(iSpeed) <= 1 && Math.abs(a) <= 1) {
console.log('over')
clearInterval(obj.timer);
obj.style.left = target + 'px';
} else {
obj.style.left = obj.offsetLeft + iSpeed + 'px';
}
}, 30);
}
25、封装自己的forEach方法
Array.prototype.myForEach = function (func, obj) {
var len = this.length;
var _this = arguments[1] ? arguments[1] : window;
// var _this=arguments[1]||window;
for (var i = 0; i < len; i++) {
func.call(_this, this[i], i, this)
}
}
26、封装自己的filter方法
Array.prototype.myFilter = function (func, obj) {
var len = this.length;
var arr = [];
var _this = arguments[1] || window;
for (var i = 0; i < len; i++) {
func.call(_this, this[i], i, this) && arr.push(this[i]);
}
return arr;
}
27、数组map方法
Array.prototype.myMap = function (func) {
var arr = [];
var len = this.length;
var _this = arguments[1] || window;
for (var i = 0; i < len; i++) {
arr.push(func.call(_this, this[i], i, this));
}
return arr;
}
28、数组every方法
Array.prototype.myEvery = function (func) {
var flag = true;
var len = this.length;
var _this = arguments[1] || window;
for (var i = 0; i < len; i++) {
if (func.apply(_this, [this[i], i, this]) == false) {
flag = false;
break;
}
}
return flag;
}
29、数组reduce方法
Array.prototype.myReduce = function (func, initialValue) {
var len = this.length,
nextValue,
i;
if (!initialValue) {
// 没有传第二个参数
nextValue = this[0];
i = 1;
} else {
// 传了第二个参数
nextValue = initialValue;
i = 0;
}
for (; i < len; i++) {
nextValue = func(nextValue, this[i], i, this);
}
return nextValue;
}
30、获取url中的参数
function getWindonHref() {
var sHref = window.location.href;
var args = sHref.split('?');
if (args[0] === sHref) {
return '';
}
var hrefarr = args[1].split('#')[0].split('&');
var obj = {};
for (var i = 0; i < hrefarr.length; i++) {
hrefarr[i] = hrefarr[i].split('=');
obj[hrefarr[i][0]] = hrefarr[i][1];
}
return obj;
}
const getParameters = (URL) => {
URL = JSON.parse(
'{"' +
decodeURI(URL.split("?")[1])
.replace(/"/g, '\\"')
.replace(/&/g, '","')
.replace(/=/g, '":"') +
'"}'
);
return JSON.stringify(URL);
};
getParameters(window.location);
// Result: { search : "easy", page : 3 }
或者更为简单的：
Object.fromEntries(new URLSearchParams(window.location.search))
// Result: { search : "easy", page : 3 }
键值对拼接成URL参数
export const params2Url = (obj) => {
let params = []
for (let key in obj) {
params.push(`${key}=${obj[key]}`);
}
return encodeURIComponent(params.join('&'))
}
31、数组排序
// 快排 [left] + min + [right]
function quickArr(arr) {
if (arr.length <= 1) {
return arr;
}
var left = [],
right = [];
var pIndex = Math.floor(arr.length / 2);
var p = arr.splice(pIndex, 1)[0];
for (var i = 0; i < arr.length; i++) {
if (arr[i] <= p) {
left.push(arr[i]);
} else {
right.push(arr[i]);
}
}
// 递归
return quickArr(left).concat([p], quickArr(right));
}
// 冒泡
function bubbleSort(arr) {
for (var i = 0; i < arr.length - 1; i++) {
for (var j = i + 1; j < arr.length; j++) {
if (arr[i] > arr[j]) {
var temp = arr[i];
arr[i] = arr[j];
arr[j] = temp;
}
}
}
return arr;
}
function bubbleSort(arr) {
var len = arr.length;
for (var i = 0; i < len - 1; i++) {
for (var j = 0; j < len - 1 - i; j++) {
if (arr[j] > arr[j + 1]) {
var temp = arr[j];
arr[j] = arr[j + 1];
arr[j + 1] = temp;
}
}
}
return arr;
}
32、遍历Dom树
// 给定页面上的DOM元素,将访问元素本身及其所有后代(不仅仅是它的直接子元素)
// 对于每个访问的元素，函数讲元素传递给提供的回调函数
function traverse(element, callback) {
callback(element);
var list = element.children;
for (var i = 0; i < list.length; i++) {
traverse(list[i], callback);
}
}
33、原生js封装ajax
function ajax(method, url, callback, data, flag) {
var xhr;
flag = flag || true;
method = method.toUpperCase();
if (window.XMLHttpRequest) {
xhr = new XMLHttpRequest();
} else {
xhr = new ActiveXObject('Microsoft.XMLHttp');
}
xhr.onreadystatechange = function () {
if (xhr.readyState == 4 && xhr.status == 200) {
console.log(2)
callback(xhr.responseText);
}
}
if (method == 'GET') {
var date = new Date(),
timer = date.getTime();
xhr.open('GET', url + '?' + data + '&timer' + timer, flag);
xhr.send()
} else if (method == 'POST') {
xhr.open('POST', url, flag);
xhr.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
xhr.send(data);
}
}
34、异步加载script
function loadScript(url, callback) {
var oscript = document.createElement('script');
if (oscript.readyState) { // ie8及以下版本
oscript.onreadystatechange = function () {
if (oscript.readyState === 'complete' || oscript.readyState === 'loaded') {
callback();
}
}
} else {
oscript.onload = function () {
callback()
};
}
oscript.src = url;
document.body.appendChild(oscript);
}
35、cookie管理
var cookie = {
set: function (name, value, time) {
document.cookie = name + '=' + value + '; max-age=' + time;
return this;
},
remove: function (name) {
return this.setCookie(name, '', -1);
},
get: function (name, callback) {
var allCookieArr = document.cookie.split('; ');
for (var i = 0; i < allCookieArr.length; i++) {
var itemCookieArr = allCookieArr[i].split('=');
if (itemCookieArr[0] === name) {
return itemCookieArr[1]
}
}
return undefined;
}
}
36、实现bind()方法
Function.prototype.myBind = function (target) {
var target = target || window;
var _args1 = [].slice.call(arguments, 1);
var self = this;
var temp = function () {};
var F = function () {
var _args2 = [].slice.call(arguments, 0);
var parasArr = _args1.concat(_args2);
return self.apply(this instanceof temp ? this : target, parasArr)
}
temp.prototype = self.prototype;
F.prototype = new temp();
return F;
}
37、实现call()方法
Function.prototype.myCall = function () {
var ctx = arguments[0] || window;
ctx.fn = this;
var args = [];
for (var i = 1; i < arguments.length; i++) {
args.push(arguments[i])
}
var result = ctx.fn(...args);
delete ctx.fn;
return result;
}
38、实现apply()方法
Function.prototype.myApply = function () {
var ctx = arguments[0] || window;
ctx.fn = this;
if (!arguments[1]) {
var result = ctx.fn();
delete ctx.fn;
return result;
}
var result = ctx.fn(...arguments[1]);
delete ctx.fn;
return result;
}
39、防抖
function debounce(handle, delay) {
var timer = null;
return function () {
var _self = this,
_args = arguments;
clearTimeout(timer);
timer = setTimeout(function () {
handle.apply(_self, _args)
}, delay)
}
}
40、节流
function throttle(handler, wait) {
var lastTime = 0;
return function (e) {
var nowTime = new Date().getTime();
if (nowTime - lastTime > wait) {
handler.apply(this, arguments);
lastTime = nowTime;
}
}
}
41、requestAnimFrame兼容性方法
window.requestAnimFrame = (function () {
return window.requestAnimationFrame ||
window.webkitRequestAnimationFrame ||
window.mozRequestAnimationFrame ||
function (callback) {
window.setTimeout(callback, 1000 / 60);
};
})();
42、cancelAnimFrame兼容性方法
window.cancelAnimFrame = (function () {
return window.cancelAnimationFrame ||
window.webkitCancelAnimationFrame ||
window.mozCancelAnimationFrame ||
function (id) {
window.clearTimeout(id);
};
})();
43、jsonp底层方法
function jsonp(url, callback) {
var oscript = document.createElement('script');
if (oscript.readyState) { // ie8及以下版本
oscript.onreadystatechange = function () {
if (oscript.readyState === 'complete' || oscript.readyState === 'loaded') {
callback();
}
}
} else {
oscript.onload = function () {
callback()
};
}
oscript.src = url;
document.body.appendChild(oscript);
}
44、获取url上的参数
function getUrlParam(sUrl, sKey) {
var result = {};
sUrl.replace(/(\w+)=(\w+)(?=[&|#])/g, function (ele, key, val) {
if (!result[key]) {
result[key] = val;
} else {
var temp = result[key];
result[key] = [].concat(temp, val);
}
})
if (!sKey) {
return result;
} else {
return result[sKey] || '';
}
}
使用URL 对象获取参数
const url =
'https://test.iha0517.net/smartCity/H5/H5Login/index.html?ak=9ce9d206-7738-40a2-bac2-3db262c40c64&inviteCode=ZCAT&type=2×tamp=1659943721974&activityName=%27%E9%82%80%E6%96%B0%E6%B4%BB%E5%8A%A8%27&activityId=%27%27#/'
const urlObj = new URL(url)
const paramsValue = urlObj.searchParams.get('activityName')
console.log(' paramsValue', paramsValue)
从 URL 中获取参数
const getParamByUrl = (key) => {
const url = new URL(location.href)
return url.searchParams.get(key)
}
45、格式化时间
function formatDate(t, str) {
var obj = {
yyyy: t.getFullYear(),
yy: ("" + t.getFullYear()).slice(-2),
M: t.getMonth() + 1,
MM: ("0" + (t.getMonth() + 1)).slice(-2),
d: t.getDate(),
dd: ("0" + t.getDate()).slice(-2),
H: t.getHours(),
HH: ("0" + t.getHours()).slice(-2),
h: t.getHours() % 12,
hh: ("0" + t.getHours() % 12).slice(-2),
m: t.getMinutes(),
mm: ("0" + t.getMinutes()).slice(-2),
s: t.getSeconds(),
ss: ("0" + t.getSeconds()).slice(-2),
w: ['日', '一', '二', '三', '四', '五', '六'][t.getDay()]
};
return str.replace(/([a-z]+)/ig, function ($1) {
return obj[$1]
});
}
46、验证邮箱的正则表达式
function isAvailableEmail(sEmail) {
var reg = /^([\w+\.])+@\w+([.]\w+)+$/
return reg.test(sEmail)
}
47、函数柯里化
//是把接受多个参数的函数变换成接受一个单一参数(最初函数的第一个参数)的函数，并且返回接受余下的参数且返回结果的新函数的技术
function curryIt(fn) {
var length = fn.length,
args = [];
var result = function (arg) {
args.push(arg);
length--;
if (length <= 0) {
return fn.apply(this, args);
} else {
return result;
}
}
return result;
}
48、大数相加
function sumBigNumber(a, b) {
var res = '', //结果
temp = 0; //按位加的结果及进位
a = a.split('');
b = b.split('');
while (a.length || b.length || temp) {
//~~按位非 1.类型转换，转换成数字 2.~~undefined==0
temp += ~~a.pop() + ~~b.pop();
res = (temp % 10) + res;
temp = temp > 9;
}
return res.replace(/^0+/, '');
}
49、单例模式
function getSingle(func) {
var result;
return function () {
if (!result) {
result = new func(arguments);
}
return result;
}
}
50、设备判断：android、ios、web
const isDevice = function() { // 判断是android还是ios还是web
var ua = navigator.userAgent.toLowerCase()
if (ua.match(/iPhone\sOS/i) === 'iphone os' || ua.match(/iPad/i) === 'ipad') { // ios
return 'iOS'
}
if (ua.match(/Android/i) === 'android') {
return 'Android'
}
return 'Web'
}
- 判断是否为微信
const isWx = function() { // 判断是否为微信
var ua = window.navigator.userAgent.toLowerCase()
if (ua.match(/MicroMessenger/i) === 'micromessenger') {
return true
}
return false
}
52.是否为PC端
const isPC = function() { // 是否为PC端
let userAgentInfo = navigator.userAgent
let Agents = ['Android', 'iPhone', 'SymbianOS', 'Windows Phone', 'iPad', 'iPod']
let flag = true
for (let v = 0; v < Agents.length; v++) {
if (userAgentInfo.indexOf(Agents[v]) > 0) {
flag = false
break
}
}
return flag
}
53.判断图片加载完成
const imgLoadAll = function(arr, callback) { // 图片加载
let arrImg = []
for (let i = 0; i < arr.length; i++) {
let img = new Image()
img.src = arr[i]
img.onload = function() {
arrImg.push(this)
if (arrImg.length == arr.length) {
callback && callback()
}
}
}
}
54.音频加载完成操作
const loadAudio = function(src, callback) { // 音频加载
var audio = new Audio(src)
audio.onloadedmetadata = callback
audio.src = src
}
55,图片地址转base64
const getBase64 = function(img) { //传入图片路径，返回base64，使用getBase64(url).then(function(base64){},function(err){});
let getBase64Image = function(img, width, height) { //width、height调用时传入具体像素值，控制大小,不传则默认图像大小
let canvas = document.createElement("canvas");
canvas.width = width ? width : img.width;
canvas.height = height ? height : img.height;
let ctx = canvas.getContext("2d");
ctx.drawImage(img, 0, 0, canvas.width, canvas.height);
let dataURL = canvas.toDataURL();
return dataURL;
}
let image = new Image();
image.crossOrigin = '';
image.src = img;
let deferred = $.Deferred();
if (img) {
image.onload = function() {
deferred.resolve(getBase64Image(image));
}
return deferred.promise();
}
}
56.H5软键盘缩回、弹起回调
const h5Resize = function(downCb, upCb) { //当软件键盘弹起会改变当前 window.innerHeight，监听这个值变化 [downCb 当软键盘弹起后，缩回的回调,upCb 当软键盘弹起的回调]
var clientHeight = window.innerHeight;
downCb = typeof downCb === 'function' ? downCb : function() {}
upCb = typeof upCb === 'function' ? upCb : function() {}
window.addEventListener('resize', () => {
var height = window.innerHeight;
if (height === clientHeight) {
downCb();
}
if (height < clientHeight) {
upCb();
}
});
}
计算2个日期之间相差多少天
const dayDif = (date1, date2) => Math.ceil(Math.abs(date1.getTime() - date2.getTime()) / 86400000)
dayDif(new Date("2020-10-21"), new Date("2021-10-22"))
// Result: 366
生成随机十六进制颜色
//可以使用 Math.random 和 padEnd 属性生成随机的十六进制颜色。
const randomHex = () => `#${Math.floor(Math.random() * 0xffffff).toString(16).padEnd(6, "0")}`;
console.log(randomHex());
// Result: #92b008
手机号中间四位变成*
export const telFormat = (tel) => {
tel = String(tel);
return tel.substr(0,3) + "****" + tel.substr(7);
}
数字转化为大写金额
export const digitUppercase = (n) => {
const fraction = ['角', '分'];
const digit = [
'零', '壹', '贰', '叁', '肆',
'伍', '陆', '柒', '捌', '玖'
];
const unit = [
['元', '万', '亿'],
['', '拾', '佰', '仟']
];
n = Math.abs(n);
let s = '';
for (let i = 0; i < fraction.length; i++) {
s += (digit[Math.floor(n * 10 * Math.pow(10, i)) % 10] + fraction[i]).replace(/零./, '');
}
s = s || '整';
n = Math.floor(n);
for (let i = 0; i < unit[0].length && n > 0; i++) {
let p = '';
for (let j = 0; j < unit[1].length && n > 0; j++) {
p = digit[n % 10] + unit[1][j] + p;
n = Math.floor(n / 10);
}
s = p.replace(/(零.)*零$/, '').replace(/^$/, '零') + unit[0][i] + s;
}
return s.replace(/(零.)*零元/, '元')
.replace(/(零.)+/g, '零')
.replace(/^整$/, '零元整');
};
数字转化为中文数字
export const intToChinese = (value) => {
const str = String(value);
const len = str.length-1;
const idxs = ['','十','百','千','万','十','百','千','亿','十','百','千','万','十','百','千','亿'];
const num = ['零','一','二','三','四','五','六','七','八','九'];
return str.replace(/([1-9]|0+)/g, ( $, $1, idx, full) => {
let pos = 0;
if($1[0] !== '0'){
pos = len-idx;
if(idx == 0 && $1[0] == 1 && idxs[len-idx] == '十'){
return idxs[len-idx];
}
return num[$1[0]] + idxs[len-idx];
} else {
let left = len - idx;
let right = len - idx + $1.length;
if(Math.floor(right / 4) - Math.floor(left / 4) > 0){
pos = left - left % 4;
}
if( pos ){
return idxs[pos] + num[$1[0]];
} else if( idx + $1.length >= len ){
return '';
}else {
return num[$1[0]]
}
}
});
}
（1）存储loalStorage
export const loalStorageSet = (key, value) => {
if (!key) return;
if (typeof value !== 'string') {
value = JSON.stringify(value);
}
window.localStorage.setItem(key, value);
};
（2）获取localStorage
export const loalStorageGet = (key) => {
if (!key) return;
return window.localStorage.getItem(key);
};
（3）删除localStorage
export const loalStorageRemove = (key) => {
if (!key) return;
window.localStorage.removeItem(key);
};
（4）存储sessionStorage
export const sessionStorageSet = (key, value) => {
if (!key) return;
if (typeof value !== 'string') {
value = JSON.stringify(value);
}
window.sessionStorage.setItem(key, value)
};
（5）获取sessionStorage
export const sessionStorageGet = (key) => {
if (!key) return;
return window.sessionStorage.getItem(key)
};
（6）删除sessionStorage
export const sessionStorageRemove = (key) => {
if (!key) return;
window.sessionStorage.removeItem(key)
};
- 操作cookie
（1）设置cookie
export const setCookie = (key, value, expire) => {
const d = new Date();
d.setDate(d.getDate() + expire);
document.cookie = `${key}=${value};expires=${d.toUTCString()}`
};
（2）读取cookie
export const getCookie = (key) => {
const cookieStr = unescape(document.cookie);
const arr = cookieStr.split('; ');
let cookieValue = '';
for (let i = 0; i < arr.length; i++) {
const temp = arr[i].split('=');
if (temp[0] === key) {
cookieValue = temp[1];
break
}
}
return cookieValue
};
（3）删除cookie
export const delCookie = (key) => {
document.cookie = `${encodeURIComponent(key)}=;expires=${new Date()}`
};
检测密码强度
export const checkPwd = (str) => {
var Lv = 0;
if (str.length < 6) {
return Lv
}
if (/[0-9]/.test(str)) {
Lv++
}
if (/[a-z]/.test(str)) {
Lv++
}
if (/[A-Z]/.test(str)) {
Lv++
}
if (/[\.|-|_]/.test(str)) {
Lv++
}
return Lv;
}
生成随机字符串（唯一ID？）
const randomString = () => Math.random().toString(36).slice(2);
console.log(randomString());
// could be anything!!!
计算两个日期之间的天数
const daysDiff = (date, date2) => Math.ceil(Math.abs(date - date2) / 86400000);
console.log(daysDiff(new Date('2021-05-10'), new Date('2021-11-25')));
// 199
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