目錄結構

一、jquery源碼中常見知識點

二、javascript中原型鏈常見的知識點

三、常用的方法集知識點

四、經典實例應用

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一、jquery源碼中常見的知識點

　　1.string，number類型轉換的快捷方法

// @param s為字符串，n為數字 function fn(obj){//轉換為String類型var s = obj +"";//轉換為number類型var n = +obj; }

　　分享一個面試例子：

//加會將其后面自動轉換成字符串 "64"+4="644" //減會將其自動轉換成數字 "64"-4=60

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　　2.bool類型轉換

　　!!obj，將其強制轉換為bool類型

alert(!!0) //結果為false alert(!!"33dd") //結果為true

　　!obj，取相反的bool類型

alert(!0) //結果為true alert(!"222333") //結果為false

　　3.=== 與 ==區別

　　=== 是嚴格相等，不會進行類型轉換，而 == 是不嚴格相等，會進行類型轉換。有些js的書中，建議開發人員永遠不要用 == 或者 != 。

　　但是jquery源碼中，有用到“==”或者“!=”的情況 —— 判斷 undefined 和 null 的時候(undefined == null為true)。

//這里的判斷，將obj是null，obj是undefined都排除在外了 if(obj != null){ }

　　4.檢測obj是否為window對象

//null == window.null為true function isWindow(obj){return obj != null && obj == window.obj; }

　　5.|| 與 && 用法技巧

//例 var aa=5; name = aa || {} ; alert(name) 則name為55 this.name = name || {} //如果name值存在，則值為name，反之為{}//例 var aa=5; name = aa && {} ; alert(name) 則name為{}，因為aa為5，不為0則為真 this.name = bool && [] //如果bool為true，則值為[],反之則為bool

　　經典實例:

( window.foo || ( window.foo = "bar" ) ); alert(window.foo); //彈出 bar
//? 為什么最后的結果是bar呢，其實可以看成是? ?undefined || bar??出來的結果肯定是bar

　　6.setTimeout(fn,0)與setTimeout(fn)區別（此處有問題，沒有考慮單線程的問題，請比較了解的大神，幫忙指點）

　　setTimeout(fn,0)與setTimeout(fn)都是延遲執行，但是setTimeout(fn)比setTimeout(fn,0)延遲時間還要長，例

function fn(){var data = new Date();for(var i=0;i<=1000;i++){if(i==1000){console.log("fn="+data.getTime());}}}function fn1(){var data = new Date();for(var i=0;i<=1000;i++){if(i==1000){console.log("fn1="+data.getTime());}}}setTimeout(fn,0),setTimeout(fn1);

　　結果：

　

　　7.判斷是否為數值

function isNumeric(obj){ return !isNaN(parseFloat(obj)) && isFinite(obj); }

　　8.判斷是否為空對象

function isEmptyObject(){var name;//遍歷不是空對象返回for (name in obj) {return false;}return true; }

　　9.檢測對象類型

　　檢測obj對象類型，返回類型,通過Object.prototype.toString()來判斷類型，但是ie低版本兼容性有問題，因此采用{}.toString來監測，返回為[object Array],[object Object],[object Function]

// 類型判斷 function isType(type){return function(o){return Object.prototype.toString.call(o) === '[object ' + type + ']';} }var isString = isType(“String”); var isObject = isType("Object"); var isArray = isType("Array");isString("I'm Barret Lee."); isArray([1,2,3])； isObject({});

　　10.jquery里的去除空格trim妙用

　

//相當于if (String.prototype.trim && “\uFEFF\xA0″.trim() !== “”)高級的瀏覽器已經支持原生的String的trim方法，但是pFan還為了避免它沒法解析全角空白，所以加多了一個判斷：”\uFEFF\xA0″.trim() !== “” vart core_version = "1.0",core_trim = core_version.trim; function trim(){core_trim && !core_trim.call("\uFEFF\xA0") ?function (text) {return text == null ?"" :core_trim.call(text); //這里按我的理解應該為" ".trim.call(text),有點不明白轉換為"1.1.0".trim.call(text) } :// 高級的瀏覽器已經支持原生的String的trim方法，如果瀏覽器不支持則采用 function (text) {var whitespace = "[\\x20\\t\\r\\n\\f]",rtrim = new RegExp("^" + whitespace + "+|((?:^|[^\\\\])(?:\\\\.)*)" + whitespace + "+$", "g");return text == null ?"" :(text + "").replace(rtrim, "");},//nodeName函數是獲取dom節點的節點名字或者判斷其名字跟傳入參數是否匹配 nodeName: function(elem,name){//IE下，DOM節點的nodeName是大寫的，例如DIVreturn elem.nodeName && elem.nodeName.toLowerCase() === name.toLowerCase();} }

　　11.jquery中檢測數組或者類數組中是否含存在傳入的值

/**檢查數組中是否存在傳入的值，如果存在就返回值所在的位置，如果不存在就返回-1。*elem 規定需檢索的值。*arr 數組*i 可選的整數參數。規定在數組中開始檢索的位置。它的合法取值是 0 到 arr.length - 1。如省略該參數，則將從數組首元素開始檢索。*/ function inArray(elem, arr, i){var len;if (arr) {//如果瀏覽器支持Array擁有indexOf方法if ([].indexOf) {return [].indexOf.call(arr, elem, i);}len = arr.length;//當i為負數的時候，從數組后邊len+i的位置開始索引//理解這個分成兩個部分i = i ? (i < 0 ? Math.max(0, len + i) : i) : 0;，i=i為true，執行(i < 0 ? Math.max(0, len + i) : i)，反正執行i=0i = i ? i < 0 ? Math.max(0, len + i) : i : 0;for (; i < len; i++) {// 雙重檢測防止類似這樣的數組 ar = [];ar[1]=1;ar[0] = undefined; 0 in ar =false;a[0]===undefined; // 0 in arr => arr[0]是否存在 'nme' in arr => arr['nme']是否存在if (i in arr && arr[i] === elem) {return i;}}}return -1; }

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二、javascript中原型鏈常見的知識點

　　1.hasOwnProperty()方法

　　?使用hasOwnProperty()方法可以檢測一個屬性是存在與實例，還是存在于原型中。這個方法從Object繼承，只在給定屬性存在于對象實例中時，才會返回true。

function Person(){this.age=25;this.job="web";}Person.prototype={name:'pingfan',sayName:function(){alert(this.name);}}var person1=new Person();//來自構造函數，檢測屬性，也返回truealert(person1.hasOwnProperty("age"));//來自原型屬性，返回falsealert(person1.hasOwnProperty("name"));person1.name='ping';//來自實例屬性，返回truealert(person1.hasOwnProperty("name"));

　　2.通過instanceOf檢查this是否為構造函數的一個實例

function shiCha(opt){//檢測this是否為對象的實例if( !(this instanceof shiCha)){return new shiCha(opt);} } var shicha1 = new shiCha(), //會返回一個shiCha對象
　　 shicha2 = shiCha(); //構造函數作為函數時與其他函數無意，this指向window

　　3.javascript中Array.prototype.slice.call(arguments)　　

　　我們通常看到Array.prototype.slice.call(arguments,1)或者Array.prototype.slice.call(arguments)，都有點摸不著頭腦，其實我們就是借助Array.prototype中slice()將arguments變成一個數組，并且使用該數組工作更方便，第二個參數是從索引值，開始將其變成數組，例Array.prototype.call("22223",2)和Array.prototype.call([1,2,3,4],2)，從字符串第二個開始。

function sliArray(array){//輸出為從索引1到索引3return Array.prototype.slice.call(array,1,3); } alert(sliArray([1,2,3,4,5,6])) //結果為2,3

　　4.利用閉包，實現單例模式，保證構造函數只實例一次

//對象之間永遠不會完全相等，除非它們是同一對象，因此即使創建一個具有完全相同成員的同類對象，它也不會與第一個對象完全相同
　　　　 var Universe;(function(){var instance;Universe = function Universe(){if(instance){return instance;}instance = this;//所有功能this.start_time = 0;this.bang = "Big";}})()var person1 = new Universe(),person2 = new Universe();alert(person1 === person2 ); //返回true

　　5.?利用空對象F，實現對象繼承，效率最高

//利用空對象做媒介，進行繼承效果最佳 function inhert(C,P){var F=function(){};F.protototype = P.prototype;C.prototype = new F();C.prototype.constructor = C; }

　　6. 構造函數設置return obj對象，會導致對象與原型鏈斷掉

　　理解這個問題，先理解一個概念，通常我們用new Object()，其實可以理解為隱式的做了三件事情：

　　　　①.創建一個空對象，var this ={}，繼承object對象的一些原有的屬性；
　　　　②.將構造函數寫的屬性掛載到創建的對象，this.name = "pfan";
　　　　③.通過new object()，返回this對象
　　 場景一

var Parent = function (){var that = {};that.name = "pfan"; that.age = "25";return that;}Parent.prototype = {contructor:"Parent",sayName:function(){alert(this.name);},sayAge:function(){alert(this.age);}} var child = Parent(),last = new Parent();console.dir(child);console.dir(last);child.sayName();last.sayName();

　　我們執行打開chrome控制臺，發現通過Parent()，new Parent()方法生成的對象原型鏈都斷裂了。

　　場景二：我們把對象的屬性掛載在this上，也達不到想要的結果，構造函數如下：

var Parent = function (){var that = {};this.name = "pfan"; this.age = "25";return that;}

　　chrome控制臺結果：

　　場景三：我們更大膽一點，直接讓that成一個對象，返回that，觀察new Parent()，出來的對象，是否擁有prototype上的方法

var Parent = function (){this.name = "pfan"; this.age = "25";var that = {name:"pfan111",age:"2511"}return that;}

　　chrome控制臺，可以看到new Parent()，實例返回的對象構造函數設置的返回對象，沒有繼承原型的prototype方法

　　

　　思考？？：如果構造函數返回Array，null，通過new 實例會出現什么情況呢？

　　1.Array，返回了一個Array對象，無法繼承prototype的原型

　　

　　2.null結果是返回繼承原型鏈的對象

　　場景四：構造函數中不返回對象，返回字符串

var Parent = function (){this.name = "pfan"; this.age = "25";return "11111";}

　　chrome控制臺：發現出來的結果，繼承了原型鏈

　　通過以上四個場景，我們得出結論：

　　　　1.構造函數里面，我們設置return 返回對象或者數組，通過new實例時，會導致原型鏈斷裂

　　　　2.構造函數里面，我們設置return 返回字符串或者null，或者alert()，通過new實例時，會直接忽略

三、javascript中常用方法集

　　1.?常見的數組操作方法

　　數組去重：

//數組去重原型 Array.prototype.unqie = function(){ var arr = this, len=this.length, obj={}, newArr=[]; while(len--){ if(obj[ arr[len] ] !== arr[len]){ obj[arr[len]] = arr[len]; newArr.push( arr[len]); } } return newArr.reverse(); }
//也可以通過變量來記錄匹配，效率更高

Array.prototype.unique = function(){
　　var arr = this,poxy,i = arr.length,newArr=[];
　　while(i--){
　　　　if(poxy != arr[i]){
　　　　　　poxy = arr[i];
　　　　　　newArr.push(arr[i]);
　　　　}
　　}
　　return newArr.reverse();
}

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　　取數組中最大值：

Array.prototype.arrMax=function(){var arr=this, len=this.length,max=arr[0];for(var i=1;i<len;i++){if(max<arr[i]){max=arr[i];}}return max; } //數組中通過sort取最大值Array.prototype.arrMax=function(){var arr=this;arr.sort(function(a,b){return a-b;})return arr[arr.length-1];}//利用Math.max取數組最大值 Array.prototype.arrMax =function(){var array = this;return Math.max.apply(null, array); } alert([1,2,3,4,5,6,9,8,7,9].arrMax());

　　取數組中最小值：

//數組中最的小值 Array.prototype.arrMin=function(){var arr=this, len=this.length,min=arr[0];for(var i=1;i<len;i++){if(min>arr[i]){min=arr[i];}}return min; } //數組中通過sort取最的小值 Array.prototype.arrSortMin=function(){var arr=this;arr.sort(function(a,b){return a-b;})return arr[0]; }//利用Math.max取數組最大值 Array.prototype.arrSortMin =function(){var array = this;return Math.min.apply(null, array); } alert([1,2,3,4,5,6,9,8,7,9].arrSortMin());

　　復制數組：

Array.prototype.copy =function() {return [].concat(this); };

　　去除數組中只指定元素，只能去除一個，如果想多個，之前先用unique處理：

Array.prototype.remove = function(value){for(var i=0,len=this.length;i<len;i++){if(this[i]==value){this.splice(i, 1);break;}}return this; }

　　判斷數組中元素出現的次數最多的一個元素和次數：　

Array.prototype.maxNum = function(){var arr = this,obj={};for(var i =0, len=arr.length;i<len;i++){var key = arr[i];if( ! obj[key]){obj[key] = 1;}else{obj[key]++;}}var max = -1,maxStr;for( key in obj){if(obj[key]>max){max = obj[key];maxStr = key;}}//alert(maxStr); maxStr為最大的元素，max為次數return [maxStr,max];}

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　　2.操作document.loaction的方法集（這里借用了園友總結的相關方法）

pFan.url = { //#URL//參數：變量名，url為空則表從當前頁面的url中取 getQuery: function (name, url) {var u = arguments[1] || window.location.search, reg = new RegExp("(^|&)" + name + "=([^&]*)(&|$)"), r = u.substr(u.indexOf("?") + 1).match(reg);return r != null ? r[2] : "";}, getHash: function (name, url) { //# 獲取 hash值var u = arguments[1] || location.hash;var reg = new RegExp("(^|&)" + name + "=([^&]*)(&|$)");var r = u.substr(u.indexOf("#") + 1).match(reg);if (r != null) {return r[2];}return "";}, parse: function (url) { //# 解析URLvar a = document.createElement('a');url = url || document.location.href;a.href = url;return {source: url, protocol: a.protocol.replace(':', ''), host: a.hostname, port: a.port, query: a.search, file: (a.pathname.match(/([^\/?#]+)$/i) || [, ''])[1], hash: a.hash.replace('#', ''), path: a.pathname.replace(/^([^\/])/, '/$1'), relative: (a.href.match(/tps?:\/\/[^\/]+(.+)/) || [, ''])[1], segments: a.pathname.replace(/^\//, '').split('/') };} };

　　3.常用的正則表達式

pFan.regExp = { //# 字符串匹配//是否為 數字！整數，浮點數isNum: function (num) { //# 是否為數組return !isNaN(num);}, isEmail: function (mail) {//# 是否為 郵箱return /^([a-z0-9]+[_\-\.]?)*[a-z0-9]+@([a-z0-9]+[_\-\.]?)*[a-z0-9]+\.[a-z]{2,5}$/i.test(mail);}, isIdCard: function (card) { //# 是否為 身份證return /^(\d{14}|\d{17})(\d|[xX])$/.test(card);}, isMobile: function (mobile) { //# 是否為 手機return /^0*1\d{10}$/.test(mobile);}, isQQ: function (qq) { //# 是否為 QQreturn /^[1-9]\d{4,10}$/.test(qq);}, isTel: function (tel) { //# 是否為 電話return /^\d{3,4}-\d{7,8}(-\d{1,6})?$/.text(tel);}, isUrl: function (url) { //# 是否為 URLreturn /https?:\/\/[a-z0-9\.\-]{1,255}\.[0-9a-z\-]{1,255}/i.test(url);}, isColor: function (color) { //# 是否為 16進制顏色return /#([\da-f]{3}){1,2}$/i.test(color);}//@id ： 身份證 ，// @now : 當前時間 如：new Date('2013/12/12') , '2013/12/12'// @age ： 允許的年齡, isAdult: function (id, allowAge, now) { //# 是否年齡是否成年var age = 0 // 用戶 年月日, nowDate = 0 //當前年月日 ;allowAge = parseFloat(allowAge) || 18;now = typeof now == 'string' ? new Date(now) : (now || new Date());if (!this.isIdCard(id)) {return false;}//15位身份證if (15 == id.length) {age = '19' + id.slice(6, 6);} else {age = id.slice(6, 14);}// 類型轉換 整型age = ~~age;nowDate = ~~(Tydic.date.format('YYYYMMDD', now));//比較年齡if (nowDate - age < allowAge * 1e4) {return false;}return true;}//浮點數, isFloat: function (num) { //# 是否為 浮點數return /^(([1-9]\d*)|(\d+\.\d+)|0)$/.test(num);}//正整數, isInt: function (num) { //# 是否為 正整數return /^[1-9]\d*$/.test(num);}//是否全為漢字, isChinese: function (str) { //# 是否全為 漢字return /^([\u4E00-\u9FA5]|[\uFE30-\uFFA0])+$/gi.test(str);}};

　　4.操作className的方法集

PFan.conClass = {hasClass:function(){return ele.className.match(new RegExp('(\\s|^)'+cls+'(\\s|$)')); },addClass:function(){if (!hasClass(ele,cls)) ele.className += " "+cls; },removeClass:function(){if (hasClass(ele,cls)) { var reg = new RegExp('(\\s|^)'+cls+'(\\s|$)'); ele.className=ele.className.replace(reg,' '); } } }

　　5.操作字符串方法

pFan.string = { //# 字符串codeHtml: function (content) { //# 轉義 HTML 字符return this.replace(content, {'&': "&amp;", '"': "&quot;", "'": '&#39;', '<': "&lt;", '>': "&gt;", ' ': "&nbsp;", '\t': "&#09;", '(': "&#40;", ')': "&#41;", '*': "&#42;", '+': "&#43;", ',': "&#44;", '-': "&#45;", '.': "&#46;", '/': "&#47;", '?': "&#63;", '\\': "&#92;", '\n': "<br>"});}//重復字符串, repeat: function (word, length, end) { //# 重復字符串end = end || ''; //加在末位length = ~~length;return new Array(length * 1 + 1).join(word) + '' + end;}//增加前綴, addPre: function (pre, word, size) { //# 補齊。如給數字前 加 0pre = pre || '0';size = parseInt(size) || 0;word = String(word || '');var length = Math.max(0, size - word.length);return this.repeat(pre, length, word);}//去除兩邊空格, trim: function (text) { //# 去除兩邊空格return (text || '').replace(/^\s+|\s$/, '');}//去除左邊空格 ,ltrim:function(){ return s.replace( /^(\s*|　*)/, ""); }//去除右邊空格 ,rtrim:function(){ return s.replace( /(\s*|　*)$/, ""); }//返回腳本內容 ,evalscript:function(s) {if(s.indexOf('<script') == -1) return s;var p = /<script[^\>]*?>([^\x00]*?)<\/script>/ig;var arr = [];while(arr = p.exec(s)) {var p1 = /<script[^\>]*?src=\"([^\>]*?)\"[^\>]*?(reload=\"1\")?(?:charset=\"([\w\-]+?)\")?><\/script>/i;var arr1 = [];arr1 = p1.exec(arr[0]);if(arr1) {appendscript(arr1[1], '', arr1[2], arr1[3]);} else {p1 = /<script(.*?)>([^\x00]+?)<\/script>/i;arr1 = p1.exec(arr[0]);appendscript('', arr1[2], arr1[1].indexOf('reload=') != -1);}}return s;}//清除腳本內容 ,stripscript:function(){return s.replace(/<script.*?>.*?<\/script>/ig, '');}//字符串替換, replace: function (str, re) { //# 字符串替換str = str || '';for (var key in re) {replace(key, re[key]);};function replace(a, b) {var arr = str.split(a);str = arr.join(b);};return str;}, xss: function (str, type) { //# XSS 轉義//空過濾if (!str) {return str === 0 ? "0" : "";}switch (type) {case "html": //過濾html字符串中的XSSreturn str.replace(/[&'"<>\/\\\-\x00-\x09\x0b-\x0c\x1f\x80-\xff]/g, function (r) {return "&#" + r.charCodeAt(0) + ";"}).replace(/ /g, "&nbsp;").replace(/\r\n/g, "<br />").replace(/\n/g, "<br />").replace(/\r/g, "<br />");break;case "htmlEp": //過濾DOM節點屬性中的XSSreturn str.replace(/[&'"<>\/\\\-\x00-\x1f\x80-\xff]/g, function (r) {return "&#" + r.charCodeAt(0) + ";"});break;case "url": //過濾urlreturn escape(str).replace(/\+/g, "%2B");break;case "miniUrl":return str.replace(/%/g, "%25");break;case "script":return str.replace(/[\\"']/g, function (r) {return "\\" + r;}).replace(/%/g, "\\x25").replace(/\n/g, "\\n").replace(/\r/g, "\\r").replace(/\x01/g, "\\x01");break;case "reg":return str.replace(/[\\\^\$\*\+\?\{\}\.\(\)\[\]]/g, function (a) {return "\\" + a;});break;default:return escape(str).replace(/[&'"<>\/\\\-\x00-\x09\x0b-\x0c\x1f\x80-\xff]/g, function (r) {return "&#" + r.charCodeAt(0) + ";"}).replace(/ /g, "&nbsp;").replace(/\r\n/g, "<br />").replace(/\n/g, "<br />").replace(/\r/g, "<br />");break;}}// badword , 過濾敏感詞//@text : 要過濾的文本 , 類型 ：字符串//@words : 敏感詞 ，類型，數組, 如 ： ['你妹', '我丟' ,'我靠']// 如果 用 正則匹配， text 長度 100萬，words 100萬，需要 4秒！, badWord: function (text, words) { //# 敏感詞過濾text = String(text || '');words = words || [];var reg = new RegExp(words.join('|'), 'g'), _self = this;return text.replace(reg, function ($0) {var length = String($0 || '').length;return _self.repeat('*', length);});}};

　　6.加密方法集

pFan.encrypt = { //# 加密md5: function (words) { //# md5 哈希算法/** Crypto-JS 3.1.2* http://code.google.com/p/crypto-js*/var CryptoJS = function (s, p) {var m = {}, l = m.lib = {}, n = function () { }, r = l.Base = { extend: function (b) { n.prototype = this; var h = new n; b && h.mixIn(b); h.hasOwnProperty("init") || (h.init = function () { h.$super.init.apply(this, arguments) }); h.init.prototype = h; h.$super = this; return h }, create: function () { var b = this.extend(); b.init.apply(b, arguments); return b }, init: function () { }, mixIn: function (b) { for (var h in b) b.hasOwnProperty(h) && (this[h] = b[h]); b.hasOwnProperty("toString") && (this.toString = b.toString) }, clone: function () { return this.init.prototype.extend(this) } }, q = l.WordArray = r.extend({ init: function (b, h) { b = this.words = b || []; this.sigBytes = h != p ? h : 4 * b.length }, toString: function (b) { return (b || t).stringify(this) }, concat: function (b) { var h = this.words, a = b.words, j = this.sigBytes; b = b.sigBytes; this.clamp(); if (j % 4) for (var g = 0; g < b; g++) h[j + g >>> 2] |= (a[g >>> 2] >>> 24 - 8 * (g % 4) & 255) << 24 - 8 * ((j + g) % 4); else if (65535 < a.length) for (g = 0; g < b; g += 4) h[j + g >>> 2] = a[g >>> 2]; else h.push.apply(h, a); this.sigBytes += b; return this }, clamp: function () { var b = this.words, h = this.sigBytes; b[h >>> 2] &= 4294967295 << 32 - 8 * (h % 4); b.length = s.ceil(h / 4) }, clone: function () { var b = r.clone.call(this); b.words = this.words.slice(0); return b }, random: function (b) { for (var h = [], a = 0; a < b; a += 4) h.push(4294967296 * s.random() | 0); return new q.init(h, b) } }), v = m.enc = {}, t = v.Hex = { stringify: function (b) { var a = b.words; b = b.sigBytes; for (var g = [], j = 0; j < b; j++) { var k = a[j >>> 2] >>> 24 - 8 * (j % 4) & 255; g.push((k >>> 4).toString(16)); g.push((k & 15).toString(16)) } return g.join("") }, parse: function (b) { for (var a = b.length, g = [], j = 0; j < a; j += 2) g[j >>> 3] |= parseInt(b.substr(j, 2), 16) << 24 - 4 * (j % 8); return new q.init(g, a / 2) } }, a = v.Latin1 = { stringify: function (b) { var a = b.words; b = b.sigBytes; for (var g = [], j = 0; j < b; j++) g.push(String.fromCharCode(a[j >>> 2] >>> 24 - 8 * (j % 4) & 255)); return g.join("") }, parse: function (b) { for (var a = b.length, g = [], j = 0; j < a; j++) g[j >>> 2] |= (b.charCodeAt(j) & 255) << 24 - 8 * (j % 4); return new q.init(g, a) } }, u = v.Utf8 = { stringify: function (b) { try { return decodeURIComponent(escape(a.stringify(b))) } catch (g) { throw Error("Malformed UTF-8 data"); } }, parse: function (b) { return a.parse(unescape(encodeURIComponent(b))) } },g = l.BufferedBlockAlgorithm = r.extend({ reset: function () { this._data = new q.init; this._nDataBytes = 0 }, _append: function (b) { "string" == typeof b && (b = u.parse(b)); this._data.concat(b); this._nDataBytes += b.sigBytes }, _process: function (b) { var a = this._data, g = a.words, j = a.sigBytes, k = this.blockSize, m = j / (4 * k), m = b ? s.ceil(m) : s.max((m | 0) - this._minBufferSize, 0); b = m * k; j = s.min(4 * b, j); if (b) { for (var l = 0; l < b; l += k) this._doProcessBlock(g, l); l = g.splice(0, b); a.sigBytes -= j } return new q.init(l, j) }, clone: function () { var b = r.clone.call(this); b._data = this._data.clone(); return b }, _minBufferSize: 0 }); l.Hasher = g.extend({ cfg: r.extend(), init: function (b) { this.cfg = this.cfg.extend(b); this.reset() }, reset: function () { g.reset.call(this); this._doReset() }, update: function (b) { this._append(b); this._process(); return this }, finalize: function (b) { b && this._append(b); return this._doFinalize() }, blockSize: 16, _createHelper: function (b) { return function (a, g) { return (new b.init(g)).finalize(a) } }, _createHmacHelper: function (b) { return function (a, g) { return (new k.HMAC.init(b, g)).finalize(a) } } }); var k = m.algo = {}; return m}(Math);(function (s) {function p(a, k, b, h, l, j, m) { a = a + (k & b | ~k & h) + l + m; return (a << j | a >>> 32 - j) + k } function m(a, k, b, h, l, j, m) { a = a + (k & h | b & ~h) + l + m; return (a << j | a >>> 32 - j) + k } function l(a, k, b, h, l, j, m) { a = a + (k ^ b ^ h) + l + m; return (a << j | a >>> 32 - j) + k } function n(a, k, b, h, l, j, m) { a = a + (b ^ (k | ~h)) + l + m; return (a << j | a >>> 32 - j) + k } for (var r = CryptoJS, q = r.lib, v = q.WordArray, t = q.Hasher, q = r.algo, a = [], u = 0; 64 > u; u++) a[u] = 4294967296 * s.abs(s.sin(u + 1)) | 0; q = q.MD5 = t.extend({_doReset: function () { this._hash = new v.init([1732584193, 4023233417, 2562383102, 271733878]) }, _doProcessBlock: function (g, k) {for (var b = 0; 16 > b; b++) { var h = k + b, w = g[h]; g[h] = (w << 8 | w >>> 24) & 16711935 | (w << 24 | w >>> 8) & 4278255360 } var b = this._hash.words, h = g[k + 0], w = g[k + 1], j = g[k + 2], q = g[k + 3], r = g[k + 4], s = g[k + 5], t = g[k + 6], u = g[k + 7], v = g[k + 8], x = g[k + 9], y = g[k + 10], z = g[k + 11], A = g[k + 12], B = g[k + 13], C = g[k + 14], D = g[k + 15], c = b[0], d = b[1], e = b[2], f = b[3], c = p(c, d, e, f, h, 7, a[0]), f = p(f, c, d, e, w, 12, a[1]), e = p(e, f, c, d, j, 17, a[2]), d = p(d, e, f, c, q, 22, a[3]), c = p(c, d, e, f, r, 7, a[4]), f = p(f, c, d, e, s, 12, a[5]), e = p(e, f, c, d, t, 17, a[6]), d = p(d, e, f, c, u, 22, a[7]), c = p(c, d, e, f, v, 7, a[8]), f = p(f, c, d, e, x, 12, a[9]), e = p(e, f, c, d, y, 17, a[10]), d = p(d, e, f, c, z, 22, a[11]), c = p(c, d, e, f, A, 7, a[12]), f = p(f, c, d, e, B, 12, a[13]), e = p(e, f, c, d, C, 17, a[14]), d = p(d, e, f, c, D, 22, a[15]), c = m(c, d, e, f, w, 5, a[16]), f = m(f, c, d, e, t, 9, a[17]), e = m(e, f, c, d, z, 14, a[18]), d = m(d, e, f, c, h, 20, a[19]), c = m(c, d, e, f, s, 5, a[20]), f = m(f, c, d, e, y, 9, a[21]), e = m(e, f, c, d, D, 14, a[22]), d = m(d, e, f, c, r, 20, a[23]), c = m(c, d, e, f, x, 5, a[24]), f = m(f, c, d, e, C, 9, a[25]), e = m(e, f, c, d, q, 14, a[26]), d = m(d, e, f, c, v, 20, a[27]), c = m(c, d, e, f, B, 5, a[28]), f = m(f, c, d, e, j, 9, a[29]), e = m(e, f, c, d, u, 14, a[30]), d = m(d, e, f, c, A, 20, a[31]), c = l(c, d, e, f, s, 4, a[32]), f = l(f, c, d, e, v, 11, a[33]), e = l(e, f, c, d, z, 16, a[34]), d = l(d, e, f, c, C, 23, a[35]), c = l(c, d, e, f, w, 4, a[36]), f = l(f, c, d, e, r, 11, a[37]), e = l(e, f, c, d, u, 16, a[38]), d = l(d, e, f, c, y, 23, a[39]), c = l(c, d, e, f, B, 4, a[40]), f = l(f, c, d, e, h, 11, a[41]), e = l(e, f, c, d, q, 16, a[42]), d = l(d, e, f, c, t, 23, a[43]), c = l(c, d, e, f, x, 4, a[44]), f = l(f, c, d, e, A, 11, a[45]), e = l(e, f, c, d, D, 16, a[46]), d = l(d, e, f, c, j, 23, a[47]), c = n(c, d, e, f, h, 6, a[48]), f = n(f, c, d, e, u, 10, a[49]), e = n(e, f, c, d,C, 15, a[50]), d = n(d, e, f, c, s, 21, a[51]), c = n(c, d, e, f, A, 6, a[52]), f = n(f, c, d, e, q, 10, a[53]), e = n(e, f, c, d, y, 15, a[54]), d = n(d, e, f, c, w, 21, a[55]), c = n(c, d, e, f, v, 6, a[56]), f = n(f, c, d, e, D, 10, a[57]), e = n(e, f, c, d, t, 15, a[58]), d = n(d, e, f, c, B, 21, a[59]), c = n(c, d, e, f, r, 6, a[60]), f = n(f, c, d, e, z, 10, a[61]), e = n(e, f, c, d, j, 15, a[62]), d = n(d, e, f, c, x, 21, a[63]); b[0] = b[0] + c | 0; b[1] = b[1] + d | 0; b[2] = b[2] + e | 0; b[3] = b[3] + f | 0}, _doFinalize: function () { var a = this._data, k = a.words, b = 8 * this._nDataBytes, h = 8 * a.sigBytes; k[h >>> 5] |= 128 << 24 - h % 32; var l = s.floor(b / 4294967296); k[(h + 64 >>> 9 << 4) + 15] = (l << 8 | l >>> 24) & 16711935 | (l << 24 | l >>> 8) & 4278255360; k[(h + 64 >>> 9 << 4) + 14] = (b << 8 | b >>> 24) & 16711935 | (b << 24 | b >>> 8) & 4278255360; a.sigBytes = 4 * (k.length + 1); this._process(); a = this._hash; k = a.words; for (b = 0; 4 > b; b++) h = k[b], k[b] = (h << 8 | h >>> 24) & 16711935 | (h << 24 | h >>> 8) & 4278255360; return a }, clone: function () { var a = t.clone.call(this); a._hash = this._hash.clone(); return a }}); r.MD5 = t._createHelper(q); r.HmacMD5 = t._createHmacHelper(q)})(Math);return CryptoJS.MD5(words).toString();}// sha1, sha1: function (words) { //# sha1 哈希算法var CryptoJS = function (e, m) { var p = {}, j = p.lib = {}, l = function () { }, f = j.Base = { extend: function (a) { l.prototype = this; var c = new l; a && c.mixIn(a); c.hasOwnProperty("init") || (c.init = function () { c.$super.init.apply(this, arguments) }); c.init.prototype = c; c.$super = this; return c }, create: function () { var a = this.extend(); a.init.apply(a, arguments); return a }, init: function () { }, mixIn: function (a) { for (var c in a) a.hasOwnProperty(c) && (this[c] = a[c]); a.hasOwnProperty("toString") && (this.toString = a.toString) }, clone: function () { return this.init.prototype.extend(this) } }, n = j.WordArray = f.extend({ init: function (a, c) { a = this.words = a || []; this.sigBytes = c != m ? c : 4 * a.length }, toString: function (a) { return (a || h).stringify(this) }, concat: function (a) { var c = this.words, q = a.words, d = this.sigBytes; a = a.sigBytes; this.clamp(); if (d % 4) for (var b = 0; b < a; b++) c[d + b >>> 2] |= (q[b >>> 2] >>> 24 - 8 * (b % 4) & 255) << 24 - 8 * ((d + b) % 4); else if (65535 < q.length) for (b = 0; b < a; b += 4) c[d + b >>> 2] = q[b >>> 2]; else c.push.apply(c, q); this.sigBytes += a; return this }, clamp: function () { var a = this.words, c = this.sigBytes; a[c >>> 2] &= 4294967295 << 32 - 8 * (c % 4); a.length = e.ceil(c / 4) }, clone: function () { var a = f.clone.call(this); a.words = this.words.slice(0); return a }, random: function (a) { for (var c = [], b = 0; b < a; b += 4) c.push(4294967296 * e.random() | 0); return new n.init(c, a) } }), b = p.enc = {}, h = b.Hex = { stringify: function (a) { var c = a.words; a = a.sigBytes; for (var b = [], d = 0; d < a; d++) { var f = c[d >>> 2] >>> 24 - 8 * (d % 4) & 255; b.push((f >>> 4).toString(16)); b.push((f & 15).toString(16)) } return b.join("") }, parse: function (a) { for (var c = a.length, b = [], d = 0; d < c; d += 2) b[d >>> 3] |= parseInt(a.substr(d, 2), 16) << 24 - 4 * (d % 8); return new n.init(b, c / 2) } }, g = b.Latin1 = { stringify: function (a) { var c = a.words; a = a.sigBytes; for (var b = [], d = 0; d < a; d++) b.push(String.fromCharCode(c[d >>> 2] >>> 24 - 8 * (d % 4) & 255)); return b.join("") }, parse: function (a) { for (var c = a.length, b = [], d = 0; d < c; d++) b[d >>> 2] |= (a.charCodeAt(d) & 255) << 24 - 8 * (d % 4); return new n.init(b, c) } }, r = b.Utf8 = { stringify: function (a) { try { return decodeURIComponent(escape(g.stringify(a))) } catch (c) { throw Error("Malformed UTF-8 data"); } }, parse: function (a) { return g.parse(unescape(encodeURIComponent(a))) } }, k = j.BufferedBlockAlgorithm = f.extend({ reset: function () { this._data = new n.init; this._nDataBytes = 0 }, _append: function (a) { "string" == typeof a && (a = r.parse(a)); this._data.concat(a); this._nDataBytes += a.sigBytes }, _process: function (a) { var c = this._data, b = c.words, d = c.sigBytes, f = this.blockSize, h = d / (4 * f), h = a ? e.ceil(h) : e.max((h | 0) - this._minBufferSize, 0); a = h * f; d = e.min(4 * a, d); if (a) { for (var g = 0; g < a; g += f) this._doProcessBlock(b, g); g = b.splice(0, a); c.sigBytes -= d } return new n.init(g, d) }, clone: function () { var a = f.clone.call(this); a._data = this._data.clone(); return a }, _minBufferSize: 0 }); j.Hasher = k.extend({ cfg: f.extend(), init: function (a) { this.cfg = this.cfg.extend(a); this.reset() }, reset: function () { k.reset.call(this); this._doReset() }, update: function (a) { this._append(a); this._process(); return this }, finalize: function (a) { a && this._append(a); return this._doFinalize() }, blockSize: 16, _createHelper: function (a) { return function (c, b) { return (new a.init(b)).finalize(c) } }, _createHmacHelper: function (a) { return function (b, f) { return (new s.HMAC.init(a, f)).finalize(b) } } }); var s = p.algo = {}; return p }(Math);(function () { var e = CryptoJS, m = e.lib, p = m.WordArray, j = m.Hasher, l = [], m = e.algo.SHA1 = j.extend({ _doReset: function () { this._hash = new p.init([1732584193, 4023233417, 2562383102, 271733878, 3285377520]) }, _doProcessBlock: function (f, n) { for (var b = this._hash.words, h = b[0], g = b[1], e = b[2], k = b[3], j = b[4], a = 0; 80 > a; a++) { if (16 > a) l[a] = f[n + a] | 0; else { var c = l[a - 3] ^ l[a - 8] ^ l[a - 14] ^ l[a - 16]; l[a] = c << 1 | c >>> 31 } c = (h << 5 | h >>> 27) + j + l[a]; c = 20 > a ? c + ((g & e | ~g & k) + 1518500249) : 40 > a ? c + ((g ^ e ^ k) + 1859775393) : 60 > a ? c + ((g & e | g & k | e & k) - 1894007588) : c + ((g ^ e ^ k) - 899497514); j = k; k = e; e = g << 30 | g >>> 2; g = h; h = c } b[0] = b[0] + h | 0; b[1] = b[1] + g | 0; b[2] = b[2] + e | 0; b[3] = b[3] + k | 0; b[4] = b[4] + j | 0 }, _doFinalize: function () { var f = this._data, e = f.words, b = 8 * this._nDataBytes, h = 8 * f.sigBytes; e[h >>> 5] |= 128 << 24 - h % 32; e[(h + 64 >>> 9 << 4) + 14] = Math.floor(b / 4294967296); e[(h + 64 >>> 9 << 4) + 15] = b; f.sigBytes = 4 * e.length; this._process(); return this._hash }, clone: function () { var e = j.clone.call(this); e._hash = this._hash.clone(); return e } }); e.SHA1 = j._createHelper(m); e.HmacSHA1 = j._createHmacHelper(m) })();return CryptoJS.SHA1(words).toString();}// time33 哈希, time33: function (words) { //# time33 哈希算法words = words || '';//哈希time33算法for (var i = 0, len = words.length, hash = 5381; i < len; ++i) {hash += (hash << 5) + words.charAt(i).charCodeAt();};return hash & 0x7fffffff;} }

　　7.日期方法集

pFan.date = { //返回時間戳 getTimeStamp:function(){var timestamp=new Date().getTime();return timestamp.toString();},//時間戳轉為日期格式//@nS為時間戳 getLocalTime: function(nS) { return new Date(parseInt(nS) * 1000).toLocaleString().substr(0,17);},//@time , 時間 , 如 new Date('2013/11/10 0:12:12')//@pre ， 星期的 前綴，如：周 ，星期//@ nums ，如：一二三四五六日getWeek: function (time, pre, nums) { //# 獲取星期幾time = typeof time == 'string' ? this.parse(time) : (time || new Date());pre = pre || '星期'; //周nums = nums || '日一二三四五六';return pre + nums[time.getDay()];},//@formatType : YYYY, YY, MM//@ time : new Date('2013/11/12')//@weeks : 日一二三四五六format: function (formatType, time, weeks) { //格式化輸出時間var pre = '0',formatType = formatType || 'YYYY-MM-DD',weeks = weeks || '日一二三四五六',time = time || new Date();//格式化時間return (formatType || '').replace(/yyyy|YYYY/g, time.getFullYear()).replace(/yy|YY/g, Tydic.string.addPre(pre, time.getFullYear() % 100), 2).replace(/mm|MM/g, Tydic.string.addPre(pre, time.getMonth() + 1, 2)).replace(/m|M/g, time.getMonth() + 1).replace(/dd|DD/g, Tydic.string.addPre(pre, time.getDate(), 2)).replace(/d|D/g, time.getDate()).replace(/hh|HH/g, Tydic.string.addPre(pre, time.getHours(), 2)).replace(/h|H/g, time.getHours()).replace(/ii|II/g, Tydic.string.addPre(pre, time.getMinutes(), 2)).replace(/i|I/g, time.getMinutes()).replace(/ss|SS/g, Tydic.string.addPre(pre, time.getSeconds(), 2)).replace(/s|S/g, time.getSeconds()).replace(/w/g, time.getDay()).replace(/W/g, weeks[time.getDay()]);} }

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四、經典實例應用

　　1.遞歸方法實現如下數列：1,1,2,3,5,8,13,21,34,55……

//a為位數 a為大于1的正整數 function diGui(a){if(a<=2){return 1;}else{return arguments.callee(a-1)+arguments.callee(a-2);}}alert(diGui(31));

?　　2.百度產生時間戳的方法

new Date()/36e5

?　　3.獲取字符串字節，一個因為字母1個字節，一個中文字符2個字節

//字節 function getBite(str){var len = str.length,i=len;while(i--){//中文字符串的charCodeAt碼大于255if(strrr[i].charCodeAt()>255)len++;}return len;}alert(getBite(strrr));

?　　4.var聲明提前的問題

var aa = 123;function alaa(){alert(aa) //結果為undefinedvar aa = "111"; //這里的聲明被提前的，但是賦值在后alert(aa); //結果為111 }alaa();

　　等價于：

var aa; alert(aa); aa=111; alert(aa);

?　　5.操作數組的問題

var arr = [1,2,3,4,5,6];var newArr = arr;arr.splice(0,3);console.log(newArr); //彈出結果為[4,5,6]　 newArr = arr，這一步其實我們像形成一種拷貝的形式，可是到我們去刪除arr數組里面的而原始，發現newArr里面的元素也減少了，所以newArr = arr，只是將newArr的數組指針指向了arr，所以操作arr時影響newArr。
解決辦法：
var arr = [1,2,3,4,5,6];var newArr = arr.slice(0);arr.splice(0,3),arr.push("111");console.log(arr); //結果[4,5,6,"111"]console.log(newArr); //結果 [1,2,3,4,5,6]

?　　6.隨機打亂數組

function shuffle(array) {return array.sort(function() {return Math.random() - 0.5}); }

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　　　　參考文字打亂數組順序：http://www.cnblogs.com/wayou/p/fisher_yates_shuffle.html

　　

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轉載于:https://www.cnblogs.com/pingfan1990/p/4309223.html

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