1颠猴,isStatic:檢測數(shù)據(jù)是不是除了符號外的原始數(shù)據(jù)
function isStatic(value) {
return(
typeof value === 'string' ||
typeof value === 'number' ||
typeof value === 'boolean' ||
typeof value === 'undefined' ||
value === null
)
}
2,isPrimitive:檢測數(shù)據(jù)是不是原始數(shù)據(jù)
function isPrimitive(value) {
return isStatic(value) || typeof value === 'symbol'
}
3坡贺,isObject:判斷數(shù)據(jù)是不是引用類型的數(shù)據(jù)(例如: arrays官辈,functions,objects遍坟,regexes拳亿,new Number(0),以及new String(''))
function isObject(value) {
let type = typeof value;
return value != null && (type == 'object' || type == 'function');
}
4政鼠,isObjectLike:檢查value是否是類對象风瘦。 如果一個值是類對象,那么它不應(yīng)該是null公般,而且typeof后的結(jié)果是“object”
function isObjectLike(value) {
return value != null && typeof value == 'object';
}
5万搔,getRawType:獲取數(shù)據(jù)類型胡桨,返回結(jié)果為Number,String瞬雹,Object昧谊,Array等
function getRawType(value) {
return Object.prototype.toString.call(value).slice(8, -1)
}
//getoRawType([]) ==> Array
6,isPlainObject:判斷數(shù)據(jù)是不是對象類型的數(shù)據(jù)
function isPlainObject(obj) {
return Object.prototype.toString.call(obj) === '[object Object]'
}
7酗捌,IsArray的:判斷數(shù)據(jù)是不是數(shù)組類型的數(shù)據(jù)
function isArray(arr) {
return Object.prototype.toString.call(arr) === '[object Array]'
}
將IsArray的掛載到陣列上
Array.isArray = Array.isArray || isArray;
8呢诬,isRegExp:判斷數(shù)據(jù)是不是正則對象
function isRegExp(value) {
return Object.prototype.toString.call(value) === '[object RegExp]'
}
9,而isDate:判斷數(shù)據(jù)是不是時間對象
function isDate(value) {
return Object.prototype.toString.call(value) === '[object Date]'
}
10胖缤,isNative:判斷值是不是瀏覽器內(nèi)置函數(shù)
內(nèi)置函數(shù)toString后的主體代碼塊為[native code]尚镰,而非內(nèi)置函數(shù)則為相關(guān)代碼,所以非內(nèi)置函數(shù)可以進(jìn)行拷貝(toString后掐頭去尾再由功能轉(zhuǎn))
function isNative(value) {
return typeof value === 'function' && /native code/.test(value.toString())
}
11哪廓,isFunction:檢查value是不是函數(shù)
function isFunction(value) {
return Object.prototype.toString.call(value) === '[object Function]'
}
12狗唉,isLength:檢查value是否為有效的類數(shù)組長度
function isLength(value) {
return typeof value == 'number' && value > -1 && value % 1 == 0 && value <= Number.MAX_SAFE_INTEGER;
}
13,isArrayLike:檢查value是否是類數(shù)組
如果一個值被認(rèn)為是類數(shù)組涡真,那么它不是一個函數(shù)分俯,并且value.length是個整數(shù),大于等于0哆料,小于或等于Number.MAX_SAFE_INTEGER缸剪。這里字符串也將被當(dāng)作類數(shù)組。
function isArrayLike(value) {
return value != null && isLength(value.length) && !isFunction(value);
}
14东亦,isEmpty:檢查值是否為空
如果是空杏节,直接返回真;如果是類數(shù)組,判斷數(shù)據(jù)長度;如果是對象對象典阵,判斷是否具有屬性;如果是其他數(shù)據(jù)拢锹,直接返回假(也可改為返回真)
function isEmpty(value) {
if (value == null) {
return true;
}
if (isArrayLike(value)) {
return !value.length;
}else if(isPlainObject(value)){
for (let key in value) {
if (hasOwnProperty.call(value, key)) {
return false;
}
}
}
return false;
}
15,緩存:記憶函數(shù):緩存函數(shù)的運算結(jié)果
function cached(fn) {
let cache = Object.create(null);
return function cachedFn(str) {
let hit = cache[str];
return hit || (cache[str] = fn(str))
}
}
16萄喳,camelize:橫線轉(zhuǎn)駝峰命名
let camelizeRE = /-(w)/g;
function camelize(str) {
return str.replace(camelizeRE, function(_, c) {
return c ? c.toUpperCase() : '';
})
}
//ab-cd-ef ==> abCdEf
//使用記憶函數(shù)
let _camelize = cached(camelize)
17,連字符:駝峰命名轉(zhuǎn)橫線命名:拆分字符串蹋半,使用 - 相連他巨,并且轉(zhuǎn)換為小寫
let hyphenateRE = /B([A-Z])/g;
function hyphenate(str){
return str.replace(hyphenateRE, '-$1').toLowerCase()
}
//abCd ==> ab-cd
//使用記憶函數(shù)
let _hyphenate = cached(hyphenate);
18,利用:字符串首位大寫
function capitalize(str){
return str.charAt(0).toUpperCase() + str.slice(1)
}
// abc ==> Abc
//使用記憶函數(shù)
let _capitalize = cached(capitalize)
19减江,延伸:將屬性混合到目標(biāo)對象中
function extend(to, _from) {
for(let key in _from) {
to[key] = _from[key];
}
return to
}
20染突,Object.assign:對象屬性復(fù)制,淺拷貝
Object.assign = Object.assign || function(){
if(arguments.length == 0) throw new TypeError('Cannot convert undefined or null to object');
let target = arguments[0],
args = Array.prototype.slice.call(arguments, 1),
key
args.forEach(function(item){
for(key in item){
item.hasOwnProperty(key) && ( target[key] = item[key] )
}
})
return target
}
使用Object.assign可以淺克隆一個對象:
let clone = Object.assign({}, target)
簡單的深克隆可以使用JSON.parse()來和JSON.stringify()辈灼,這兩個API是解析JSON數(shù)據(jù)的份企,所以只能解析除符號外的原始類型及數(shù)組和對象
let clone = JSON.parse( JSON.stringify(target) )
21,克卵灿ā:克隆數(shù)據(jù)司志,可深度克隆
這里列出了原始類型甜紫,時間,正則骂远,錯誤囚霸,數(shù)組,對象的克隆規(guī)則激才,其他的可自行補充
function clone(value, deep){
if(isPrimitive(value)){
return value
}
if (isArrayLike(value)) { //是類數(shù)組
value = Array.prototype.slice.call(value)
return value.map(item => deep ? clone(item, deep) : item)
}else if(isPlainObject(value)){ //是對象
let target = {}, key;
for (key in value) {
value.hasOwnProperty(key) && ( target[key] = deep ? clone(value[key], deep) : value[key] )
}
}
let type = getRawType(value)
switch(type){
case 'Date':
case 'RegExp':
case 'Error': value = new window[type](value); break;
}
return value
}
22拓型,識別各種瀏覽器及平臺
//運行環(huán)境是瀏覽器
let inBrowser = typeof window !== 'undefined';
//運行環(huán)境是微信
let inWeex = typeof WXEnvironment !== 'undefined' && !!WXEnvironment.platform;
let weexPlatform = inWeex && WXEnvironment.platform.toLowerCase();
//瀏覽器 UA 判斷
let UA = inBrowser && window.navigator.userAgent.toLowerCase();
let isIE = UA && /msie|trident/.test(UA);
let isIE9 = UA && UA.indexOf('msie 9.0') > 0;
let isEdge = UA && UA.indexOf('edge/') > 0;
let isAndroid = (UA && UA.indexOf('android') > 0) || (weexPlatform === 'android');
let isIOS = (UA && /iphone|ipad|ipod|ios/.test(UA)) || (weexPlatform === 'ios');
let isChrome = UA && /chrome/d+/.test(UA) && !isEdge;
23,getExplorerInfo:獲取瀏覽器信息
function getExplorerInfo() {
let t = navigator.userAgent.toLowerCase();
return 0 <= t.indexOf("msie") ? { //ie < 11
type: "IE",
version: Number(t.match(/msie ([d]+)/)[1])
} : !!t.match(/trident/.+?rv:(([d.]+))/) ? { // ie 11
type: "IE",
version: 11
} : 0 <= t.indexOf("edge") ? {
type: "Edge",
version: Number(t.match(/edge/([d]+)/)[1])
} : 0 <= t.indexOf("firefox") ? {
type: "Firefox",
version: Number(t.match(/firefox/([d]+)/)[1])
} : 0 <= t.indexOf("chrome") ? {
type: "Chrome",
version: Number(t.match(/chrome/([d]+)/)[1])
} : 0 <= t.indexOf("opera") ? {
type: "Opera",
version: Number(t.match(/opera.([d]+)/)[1])
} : 0 <= t.indexOf("Safari") ? {
type: "Safari",
version: Number(t.match(/version/([d]+)/)[1])
} : {
type: t,
version: -1
}
}
24瘸恼,isPCBroswer:檢測是否為PC端瀏覽器模式
function isPCBroswer() {
let e = navigator.userAgent.toLowerCase()
, t = "ipad" == e.match(/ipad/i)
, i = "iphone" == e.match(/iphone/i)
, r = "midp" == e.match(/midp/i)
, n = "rv:1.2.3.4" == e.match(/rv:1.2.3.4/i)
, a = "ucweb" == e.match(/ucweb/i)
, o = "android" == e.match(/android/i)
, s = "windows ce" == e.match(/windows ce/i)
, l = "windows mobile" == e.match(/windows mobile/i);
return !(t || i || r || n || a || o || s || l)
}
25劣挫,獨特的:數(shù)組去重,返回一個新數(shù)組
function unique(arr){
if(!isArrayLink(arr)){ //不是類數(shù)組對象
return arr
}
let result = []
let objarr = []
let obj = Object.create(null)
arr.forEach(item => {
if(isStatic(item)){//是除了symbol外的原始數(shù)據(jù)
let key = item + '_' + getRawType(item);
if(!obj[key]){
obj[key] = true
result.push(item)
}
}else{//引用類型及symbol
if(!objarr.includes(item)){
objarr.push(item)
result.push(item)
}
}
})
return resulte
}
26东帅,設(shè)置簡單實現(xiàn)
window.Set = window.Set || (function () {
function Set(arr) {
this.items = arr ? unique(arr) : [];
this.size = this.items.length; // Array的大小
}
Set.prototype = {
add: function (value) {
// 添加元素,若元素已存在,則跳過压固,返回 Set 結(jié)構(gòu)本身。
if (!this.has(value)) {
this.items.push(value);
this.size++;
}
return this;
},
clear: function () {
//清除所有成員冰啃,沒有返回值邓夕。
this.items = []
this.size = 0
},
delete: function (value) {
//刪除某個值,返回一個布爾值阎毅,表示刪除是否成功焚刚。
return this.items.some((v, i) => {
if(v === value){
this.items.splice(i,1)
return true
}
return false
})
},
has: function (value) {
//返回一個布爾值,表示該值是否為Set的成員扇调。
return this.items.some(v => v === value)
},
values: function () {
return this.items
},
}
return Set;
}());
27矿咕,重復(fù):生成一個重復(fù)的字符串,有?個STR組成狼钮,可修改為填充為數(shù)組等
function repeat(str, n) {
let res = '';
while(n) {
if(n % 2 === 1) {
res += str;
}
if(n > 1) {
str += str;
}
n >>= 1;
}
return res
};
//repeat('123',3) ==> 123123123
28碳柱,dateFormater:格式化時間
function dateFormater(formater, t){
let date = t ? new Date(t) : new Date(),
Y = date.getFullYear() + '',
M = date.getMonth() + 1,
D = date.getDate(),
H = date.getHours(),
m = date.getMinutes(),
s = date.getSeconds();
return formater.replace(/YYYY|yyyy/g,Y)
.replace(/YY|yy/g,Y.substr(2,2))
.replace(/MM/g,(M<10?'0':'') + M)
.replace(/DD/g,(D<10?'0':'') + D)
.replace(/HH|hh/g,(H<10?'0':'') + H)
.replace(/mm/g,(m<10?'0':'') + m)
.replace(/ss/g,(s<10?'0':'') + s)
}
// dateFormater('YYYY-MM-DD HH:mm', t) ==> 2019-06-26 18:30
// dateFormater('YYYYMMDDHHmm', t) ==> 201906261830
29,dateStrForma:將指定字符串由一種時間格式轉(zhuǎn)化為另一種
從的格式應(yīng)對應(yīng)海峽的位置
function dateStrForma(str, from, to){
//'20190626' 'YYYYMMDD' 'YYYY年MM月DD日'
str += ''
let Y = ''
if(~(Y = from.indexOf('YYYY'))){
Y = str.substr(Y, 4)
to = to.replace(/YYYY|yyyy/g,Y)
}else if(~(Y = from.indexOf('YY'))){
Y = str.substr(Y, 2)
to = to.replace(/YY|yy/g,Y)
}
let k,i
['M','D','H','h','m','s'].forEach(s =>{
i = from.indexOf(s+s)
k = ~i ? str.substr(i, 2) : ''
to = to.replace(s+s, k)
})
return to
}
// dateStrForma('20190626', 'YYYYMMDD', 'YYYY年MM月DD日') ==> 2019年06月26日
// dateStrForma('121220190626', '----YYYYMMDD', 'YYYY年MM月DD日') ==> 2019年06月26日
// dateStrForma('2019年06月26日', 'YYYY年MM月DD日', 'YYYYMMDD') ==> 20190626
// 一般的也可以使用正則來實現(xiàn)
//'2019年06月26日'.replace(/(d{4})年(d{2})月(d{2})日/, '$1-$2-$3') ==> 2019-06-26
30熬芜,getPropByPath:根據(jù)字符串路徑獲取對象屬性:'obj [0] .count'
function getPropByPath(obj, path, strict) {
let tempObj = obj;
path = path.replace(/[(w+)]/g, '.$1'); //將[0]轉(zhuǎn)化為.0
path = path.replace(/^./, ''); //去除開頭的.
let keyArr = path.split('.'); //根據(jù).切割
let i = 0;
for (let len = keyArr.length; i < len - 1; ++i) {
if (!tempObj && !strict) break;
let key = keyArr[i];
if (key in tempObj) {
tempObj = tempObj[key];
} else {
if (strict) {//開啟嚴(yán)格模式莲镣,沒找到對應(yīng)key值,拋出錯誤
throw new Error('please transfer a valid prop path to form item!');
}
break;
}
}
return {
o: tempObj, //原始數(shù)據(jù)
k: keyArr[i], //key值
v: tempObj ? tempObj[keyArr[i]] : null // key值對應(yīng)的值
};
};
31涎拉,GetUrlParam:獲取地址參數(shù)瑞侮,返回一個對象
function GetUrlParam(){
let url = document.location.toString();
let arrObj = url.split("?");
let params = Object.create(null)
if (arrObj.length > 1){
arrObj = arrObj[1].split("&");
arrObj.forEach(item=>{
item = item.split("=");
params[item[0]] = item[1]
})
}
return params;
}
// ?a=1&b=2&c=3 ==> {a: "1", b: "2", c: "3"}
32,downloadFile:base64數(shù)據(jù)導(dǎo)出文件鼓拧,文件下載
function downloadFile(filename, data){
let DownloadLink = document.createElement('a');
if ( DownloadLink ){
document.body.appendChild(DownloadLink);
DownloadLink.style = 'display: none';
DownloadLink.download = filename;
DownloadLink.href = data;
if ( document.createEvent ){
let DownloadEvt = document.createEvent('MouseEvents');
DownloadEvt.initEvent('click', true, false);
DownloadLink.dispatchEvent(DownloadEvt);
}
else if ( document.createEventObject )
DownloadLink.fireEvent('onclick');
else if (typeof DownloadLink.onclick == 'function' )
DownloadLink.onclick();
document.body.removeChild(DownloadLink);
}
}
33半火,toFullScreen:全屏
function toFullScreen(){
let elem = document.body;
elem.webkitRequestFullScreen
? elem.webkitRequestFullScreen()
: elem.mozRequestFullScreen
? elem.mozRequestFullScreen()
: elem.msRequestFullscreen
? elem.msRequestFullscreen()
: elem.requestFullScreen
? elem.requestFullScreen()
: alert("瀏覽器不支持全屏");
}
34,exitFullscreen:退出全屏
function exitFullscreen(){
let elem = parent.document;
elem.webkitCancelFullScreen
? elem.webkitCancelFullScreen()
: elem.mozCancelFullScreen
? elem.mozCancelFullScreen()
: elem.cancelFullScreen
? elem.cancelFullScreen()
: elem.msExitFullscreen
? elem.msExitFullscreen()
: elem.exitFullscreen
? elem.exitFullscreen()
: alert("切換失敗,可嘗試Esc退出");
}
35季俩,requestAnimationFrame:window動畫
window.requestAnimationFrame = window.requestAnimationFrame ||
window.webkitRequestAnimationFrame ||
window.mozRequestAnimationFrame ||
window.msRequestAnimationFrame ||
window.oRequestAnimationFrame ||
function (callback) {
//為了使setTimteout的盡可能的接近每秒60幀的效果
window.setTimeout(callback, 1000 / 60);
};
window.cancelAnimationFrame = window.cancelAnimationFrame ||
Window.webkitCancelAnimationFrame ||
window.mozCancelAnimationFrame ||
window.msCancelAnimationFrame ||
window.oCancelAnimationFrame ||
function (id) {
//為了使setTimteout的盡可能的接近每秒60幀的效果
window.clearTimeout(id);
}
36钮糖,_isNaN:檢查數(shù)據(jù)是否是非數(shù)字值
原生的isNaN會把參數(shù)轉(zhuǎn)換成數(shù)字(的valueOf),而空酌住,TRUE店归,F(xiàn)ALSE以及長度小于等于1的數(shù)組(元素為非NaN的數(shù)據(jù))會被轉(zhuǎn)換成數(shù)字阎抒,這不是我想要的.Symbol類型的數(shù)據(jù)不具有的valueOf接口,所以isNaN會拋出錯誤娱节,這里放在后面挠蛉,可避免錯誤
function _isNaN(v){
return !(typeof v === 'string' || typeof v === 'number') || isNaN(v)
}
37,最大:求取數(shù)組中非NaN的數(shù)據(jù)中的最大值
function max(arr){
arr = arr.filter(item => !_isNaN(item))
return arr.length ? Math.max.apply(null, arr) : undefined
}
//max([1, 2, '11', null, 'fdf', []]) ==> 11
38肄满,分鐘:求取數(shù)組中非NaN的數(shù)據(jù)中的最小值
function min(arr){
arr = arr.filter(item => !_isNaN(item))
return arr.length ? Math.min.apply(null, arr) : undefined
}
//min([1, 2, '11', null, 'fdf', []]) ==> 1
39谴古,隨機(jī):返回一個lower - upper之間的隨機(jī)數(shù)
下限,上限無論正負(fù)與大小稠歉,但必須是非的NaN的數(shù)據(jù)
function random(lower, upper){
lower = +lower || 0
upper = +upper || 0
return Math.random() * (upper - lower) + lower;
}
//random(0, 0.5) ==> 0.3567039135734613
//random(2, 1) ===> 1.6718418553475423
//random(-2, -1) ==> -1.4474325452361945
40掰担,Object.keys:返回一個由一個給定對象的自身可枚舉屬性組成的數(shù)組
Object.keys = Object.keys || function keys(object) {
if(object === null || object === undefined){
throw new TypeError('Cannot convert undefined or null to object');
}
let result = []
if(isArrayLike(object) || isPlainObject(object)){
for (let key in object) {
object.hasOwnProperty(key) && ( result.push(key) )
}
}
return result
}
41,Object.values:返回一個給定對象自身的所有可枚舉屬性值的數(shù)組
Object.values = Object.values || function values(object) {
if(object === null || object === undefined){
throw new TypeError('Cannot convert undefined or null to object');
}
let result = []
if(isArrayLike(object) || isPlainObject(object)){
for (let key in object) {
object.hasOwnProperty(key) && ( result.push(object[key]) )
}
}
return result
}
42怒炸,arr.fill:使用值值來填充數(shù)組带饱,從起始位置開始,到結(jié)束位置結(jié)束(但不包含end位置)阅羹,返回原數(shù)組
Array.prototype.fill = Array.prototype.fill || function fill(value, start, end) {
let ctx = this
let length = ctx.length;
start = parseInt(start)
if(isNaN(start)){
start = 0
}else if (start < 0) {
start = -start > length ? 0 : (length + start);
}
end = parseInt(end)
if(isNaN(end) || end > length){
end = length
}else if (end < 0) {
end += length;
}
while (start < end) {
ctx[start++] = value;
}
return ctx;
}
//Array(3).fill(2) ===> [2, 2, 2]
43勺疼,arr.includes:用來判斷一個數(shù)組是否包含一個指定的值,如果是返回true捏鱼,否則false执庐,可指定開始查詢的位置
Array.prototype.includes = Array.prototype.includes || function includes(value, start){
let ctx = this
let length = ctx.length;
start = parseInt(start)
if(isNaN(start)){
start = 0
}else if (start < 0) {
start = -start > length ? 0 : (length + start);
}
let index = ctx.indexOf(value)
return index >= start;
}
44,arr.find:返回數(shù)組中通過測試(函數(shù)FN內(nèi)判斷)的第一個元素的值
Array.prototype.find = Array.prototype.find || function find(fn, ctx){
ctx = ctx || this
let result;
ctx.some((value, index, arr), thisValue) => {
return fn(value, index, arr) ? (result = value, true) : false
})
return result
}
45导梆,arr.findIndex:返回數(shù)組中通過測試(函數(shù)fn內(nèi)判斷)的第一個元素的下標(biāo)
Array.prototype.findIndex = Array.prototype.findIndex || function findIndex(fn, ctx){
ctx = ctx || this
let result;
ctx.some((value, index, arr), thisValue) => {
return fn(value, index, arr) ? (result = index, true) : false
})
return result
}
46轨淌,performance.timing:利用performance.timing進(jìn)行性能分析
window.onload = function(){
setTimeout(function(){
let t = performance.timing
console.log('DNS查詢耗時 :' + (t.domainLookupEnd - t.domainLookupStart).toFixed(0))
console.log('TCP鏈接耗時 :' + (t.connectEnd - t.connectStart).toFixed(0))
console.log('request請求耗時 :' + (t.responseEnd - t.responseStart).toFixed(0))
console.log('解析dom樹耗時 :' + (t.domComplete - t.domInteractive).toFixed(0))
console.log('白屏?xí)r間 :' + (t.responseStart - t.navigationStart).toFixed(0))
console.log('domready時間 :' + (t.domContentLoadedEventEnd - t.navigationStart).toFixed(0))
console.log('onload時間 :' + (t.loadEventEnd - t.navigationStart).toFixed(0))
if(t = performance.memory){
console.log('js內(nèi)存使用占比 :' + (t.usedJSHeapSize / t.totalJSHeapSize * 100).toFixed(2) + '%')
}
})
}
47,禁止某些鍵盤事件
document.addEventListener('keydown', function(event){
return !(
112 == event.keyCode || //F1
123 == event.keyCode || //F12
event.ctrlKey && 82 == event.keyCode || //ctrl + R
event.ctrlKey && 78 == event.keyCode || //ctrl + N
event.shiftKey && 121 == event.keyCode || //shift + F10
event.altKey && 115 == event.keyCode || //alt + F4
"A" == event.srcElement.tagName && event.shiftKey //shift + 點擊a標(biāo)簽
) || (event.returnValue = false)
});
48看尼,禁止右鍵递鹉,選擇,復(fù)制
['contextmenu', 'selectstart', 'copy'].forEach(function(ev){
document.addEventListener(ev, function(event){
return event.returnValue = false
})
});