面向对象Javascript核心支持代码

    JQury框架绝对是首先页面开发的首选，代码短小强悍，缺点就是面向对象特性不足，所幸有不少插件!至于Ext就是一个庞然大物了，高度面向对象，类似于MFC的庞大API和控件库，运行起来，浏览器就累得够呛，开发也够呛，使用代码来创建界面绝对是个糟糕的方式，Javascript的弱语言类型使得Ext开发就像行走在雷区，减少bug的唯一方法就是不要写出bug，一旦出现bug，调试将是一件极为痛苦的事情 ！在几千行代码里跟踪、跳转真让人抓狂！

     Javascript做面向对象开发的时候，总是会用到很多模拟面向对象特性的方法，这些方法就构成了支撑面向对象Javascript的核心代码，以下就是部分代码，其中参考了很多JQuery与Ext的核心代码，用来学习还不错，也可以做一些小的开发！

/*
功能：核心脚本方法
作者：LQB

2008-12-22
*/
var JCore = {//构造核心对象
    version:1.0,
    $import:function(importFile){
        var file = importFile.toString();
        var IsRelativePath = (file.indexOf("$")==0 ||file.indexOf("/")==-1);//相对路径(相对于JCore)
        var path=file;
        if(IsRelativePath){//计算路径
            if(file.indexOf("$")==0)
                file = file.substr(1);
            path = JCore.$dir+file;
        }
        var newElement=null,i=0;
        var ext = path.substr(path.lastIndexOf(".")+1);
        if(ext.toLowerCase()=="js"){
            var scriptTags = document.getElementsByTagName("script");
            for(var i=0;i
   
    length;i++) {  
                
    if(scriptTags[i].src && scriptTags[i].src.indexOf(path)!=-1)
                    
    return;
            }
            newElement=
    document.createElement("
    script");
            newElement.type="
    text/javascript";
            newElement.src=path;
        }
        
    else 
    if(ext.toLowerCase()=="
    css"){
            
    var linkTags = 
    document.getElementsByTagName("
    link");
            
    for(
    var i=0;i
    
     length;i++) { 
     if(linkTags[i].href && linkTags[i].href.indexOf(path)!=-1) 
     return; } newElement=
     document.createElement("
     link"); newElement.type="
     text/css"; newElement.rel="
     Stylesheet"; newElement.href=path; } 
     else 
     return; 
     var head=
     document.getElementsByTagName("
     head")[0]; head.appendChild(newElement); }, $dir : 
     function(){ 
     var scriptTags = 
     document.getElementsByTagName("
     script"); 
     for(
     var i=0;i
     
      length;i++) { 
      if(scriptTags[i].src && scriptTags[i].src.match(/JCore/.js$/)) { path = scriptTags[i].src.replace(/JCore/.js$/,"
      "); 
      return path; } } 
      return "
      "; }(), $ : 
      function(element){ 
      return (
      typeof(element) == 'object' ? element : 
      document.getElementById(element)); }, browser : { isFirefox:navigator.userAgent.toLowerCase().indexOf ('gecko') != -1, isChrome:navigator.userAgent.toLowerCase().indexOf ('chrome') != -1, isOpera:navigator.userAgent.toLowerCase().indexOf ('opera') != -1, isIE:navigator.userAgent.toLowerCase().indexOf ('msie') != -1, isIE7:navigator.userAgent.toLowerCase().indexOf ('7.0') != -1 }, onReady: 
      function(newFunction){ 
      if(
      typeof(newFunction) == 'undefined') 
      return 
      false; 
      this.domReady = 
      false; 
      if(
      typeof(functions) == 'undefined') 
      var functions = []; functions.push(newFunction); 
      var initial = 
      function(){
      //执行事件列表 
      for(
      var i=0; i< functions.
      length;i++){ functions[i](); } } 
      this.ready = 
      function(){
      //加载事件 
      if(
      this.domReady) initial(); 
      var Browser = JCore.browser; 
      if (Browser.isFirefox || Browser.isOpera || Browser.isChrome) {
      //FX 
      try { 
      document.removeEventListener('DOMContentLoaded', initial); }
      catch(e){} 
      document.addEventListener('DOMContentLoaded', initial, 
      false); 
      this.domReady = 
      true; } 
      else 
      if (Browser.isIE) {
      //IE 
      var timer = 
      window.
      setInterval(
      function(){ 
      try { 
      var IsReady = 
      false; 
      document.body.doScroll("
      left"); IsReady=
      true; initial(); 
      window.
      clearInterval(timer); 
      this.domReady = 
      true; } 
      catch (e){ 
      if(IsReady){
      //文档加载已经完毕，抛出异常说明是调用的方法出错 
      var ErrorMsg = "
      onReady的方法中发生错误！/r/n"; ErrorMsg+="
      错误信息:"+e.message+"
      /r/n"; ErrorMsg+="
      错误描述:"+e.description+"
      /r/n"; ErrorMsg+="
      错误类型:"+e.
      name+"
      /r/n"; 
      alert(ErrorMsg); 
      window.
      clearInterval(timer); } } } , 5); } } 
      this.ready(); }, apply:
      function(oDes, oSrc,bReplace){
      //为对象拷贝其它对象的属性,bReplace可选 
      if(oDes && oSrc && 
      typeof(oSrc) == 'object'){ 
      for(
      var p 
      in oSrc){ 
      if(bReplace == 
      false && oDes[p] != 
      null) { 
      continue; } oDes[p] = oSrc[p]; } } 
      return oDes; }, override : 
      function(origclass, overrides){
      //为类增加重载方法，eg：override(function class(){},{A:function(){},B:function(){}}); 
      if(overrides){ 
      var p = origclass.
      prototype; 
      for(
      var method 
      in overrides){ p[method] = overrides[method]; } } }, extend :
      function(){ 
      // inline overrides 
      var inlineOverride = 
      function(o){ 
      for (
      var m 
      in o) { 
      this[m] = o[m]; } }; 
      /*需要实现重载的基类方法需要在父类prototype中定义; * 在子类中方法的可见度：子类构造中的属性>父类构造中的属性>子类prototype定义的属性==overrides>父类prototype定义的属性 * 由于overrides方法被附加到子类的prototype中，所以：子类prototype定义的属性与overrides，两者后定义的可见 * extend方法将重写子类的prototype，因此在子类的prototype上定义属性则必须在extend()方法调用之后再定义才有效 * 对于一个类：构造中定义的属性>prototype定义的属性 * *类派生的准则： * 1.建议把基类中可重写的方法定义在基类prototype中 * 2.如果在派生类的prototype中定义属性方法，必须在extend()方法之后 * 3.在派生类的构造中调用基类的构造： * if(Sub.superclass) //sub即子类的名称 * Sub.superclass.constructor.call(this, Args);//Args即父类的构造方法的参数 * 4.注意数组的浅拷贝问题 *示例： * var ClassA=function(){this.Show=function(){alert("Hello World!");}}; * var ClassB=function(){}; * JCore.extend(ClassB,ClassA); * var ObjectB = new ClassB(); * ObjectB.Show(); */ 
      return 
      function(subFn, superFn, overrides){
      //子类，父类，重载方法(可选) 
      var F = 
      function(){}, subFnPrototype, superFnPrototype = superFn.
      prototype; F.
      prototype = superFnPrototype; subFnPrototype = subFn.
      prototype = 
      new F(); subFnPrototype.
      constructor = subFn; subFn.superclass = superFnPrototype;
      //父类 
      if (superFnPrototype.
      constructor == Object.
      prototype.
      constructor) { superFnPrototype.
      constructor = superFn; } subFn.override = 
      function(obj){
      //override JCore.override(subFn, obj); }; subFnPrototype.override = inlineOverride; 
      if(overrides) JCore.override(subFn, overrides); 
      return subFn; }; }(),
      //括号不可少，表示调用内部返回的方法 namespace : 
      function(ns){
      //eg: JCore.namespace("JCore", "JCore.util"); 
      var args=
      arguments, o=
      null, i, j, d, rt; 
      for (i=0; i
      
       length; ++i) {
       //遍历参数 d=args[i].split("
       .");
       //遍历点分隔符 rt = d[0]; 
       eval('
       if (
       typeof ' + rt + ' == "
       undefined"){' + rt + ' = {};} o = ' + rt + ';'); 
       for (j=1; j
       
        length; ++j) { o[d[j]]=o[d[j]] || {}; o=o[d[j]]; } } }, isEmpty : 
        function(value){ 
        return value === 
        null || 
        typeof(value) === 'undefined' || value === ''; }, idSeed : 0, id : 
        function(el, prefix){ prefix = prefix || "
        JCore-gen"; el = 
        this.$(el); 
        var id = prefix + (
        this.idSeed++); 
        return el ? (el.id ? el.id : (el.id = id)) : id; } }; 
        /*--------------------------------------------Function对象扩展-------------------------------------------*/ 
        var FunctionExtendMethod ={ createCallback : 
        function(
        /*args...*/){
        //此参数即创造者的参数 
        /*示例：function func1(arg1,arg2){alert(arg1+arg2);} * var myfunc = func1.createCallback(1,2); * myfunc();//即调用了func1 **/ 
        var args = 
        arguments; 
        var method = 
        this; 
        return 
        function(
        /*args...*/) {
        //如果在调用时传了参数，则创建时传的参数无效 
        var callArgs = 
        arguments.
        length>0 ? 
        arguments : args; 
        return method.apply(
        window, callArgs); }; }, createDelegate : 
        function(argsArray,scope){
        //参数可选 
        //参数一个数组，与createCallback区别：createCallback参数是可变参数，createDelegate的argsArray参数必须是数组 
        var method = 
        this; 
        return 
        function(
        /*args...*/) {
        //如果在调用时传了参数，则创建时传的参数无效 
        var callArgs = 
        typeof(argsArray)=="
        undefined"?[]:argsArray; callArgs = 
        arguments.
        length>0 ? 
        arguments : callArgs; 
        return method.apply(scope||
        window, callArgs); }; }, defer : 
        function(millis
        /*,args...*/){
        //参数:延迟时间(毫秒)，可选参数列表 
        /*示例：function func1(arg1,arg2){alert(arg1+arg2);} * func1.defer(1000,1,2);//延迟1秒调用了func1(1,2) **/ 
        var callArgs = 
        Array.
        prototype.slice.call(
        arguments, 1); 
        var fn = 
        this.createDelegate(callArgs); 
        if(millis){ 
        return 
        setTimeout(fn, millis); } fn(); 
        return 0; }, createInterceptor : 
        function(fcn, scope){ 
        if(
        typeof fcn != "
        function"){ 
        return 
        this; } 
        var method = 
        this; 
        return 
        function() { fcn.target = 
        this; fcn.method = method; 
        if(fcn.apply(scope || 
        this || 
        window, 
        arguments) === 
        false){ 
        return; } 
        return method.apply(
        this || 
        window, 
        arguments); }; } }; JCore.apply(
        Function.
        prototype,FunctionExtendMethod); 
        /*--------------------------------------------String对象扩展----------------------------------------*/ 
        var StringExtendMethod ={ trim : 
        function(){
        //去掉首尾空格 
        return 
        this.replace(/(^/s*)|(/s*$)/g,"
        ");
        //将字符串前后空格,用空字符串替代。 }, replaceAll : 
        function (AFindText,ARepText){
        //替换所有,replace只替换第一个 raRegExp = 
        new 
        RegExp(AFindText,"
        g"); 
        return 
        this.replace(raRegExp,ARepText); }, htmlEncode : 
        function(){
        //编码HTML和解码Html。过滤掉双引号，单引号，符号&，符号<，符号 
        return 
        this.replace(/&/g,"
        &").replace(/<").replace(/>/g,"
        >").replace(//"
        /g,"""
        ).replace(//'/g,"'"
        ); }, htmlDecode : 
        function(){ 
        return 
        this.replace(//&/;/g, '/&').replace(//>/;/g, '/>').replace(//</;/g, '/<').replace(//"/;/g, '/'').replace(//&/#39/;/g, '/''); }, format : 
        function(){ 
        var args=
        arguments; 
        return 
        this.replace(//{(/d+)/}/g, 
        function(m, i){ 
        return args[i]; }); }, convertWarpSymbol : 
        function(){ 
        var reg1,reg2,reg3; 
        if(
        this.toLowerCase().indexOf("
        
         
          ")!=-1){ reg1 = / /gi; reg2 = /
          
           /gi; 
           return 
           this.replace(reg1,"
            ").replace(reg2,"
           /r/n"); } 
           else{ reg1 = / /g;reg2 = //r/n/gi; 
           return 
           this.replace(reg1,"
            ").replace(reg2,"
           
"); } }, IsNum : 
           function(){ 
           var reg = /^/d+$/g; 
           return reg.test(
           this); } }; JCore.apply(
           String.
           prototype,StringExtendMethod); JCore.apply(
           String,{
           //静态方法 trim : 
           function(str){
           //去掉首尾空格 
           return str.replace(/(^/s*)|(/s*$)/g,"
           ");
           //将字符串前后空格,用空字符串替代。 } }); 
           /*--------------------------------------------Array对象扩展----------------------------------------*/ 
           var ArrayExtendMethod ={
           //去掉数组中重复的元素 strip : 
           function(){ 
           if(
           this.
           length<2) 
           return [
           this[0]]||[]; 
           var arr=[]; 
           for(
           var i=0;i<
           this.
           length;i++){ 
           var repeat=
           false; 
           for(
           var j=0;j
           
            length
           
          
         ;j++){ 
        if(
        this[i]===arr[j]) repeat=
        true; } 
        if(!repeat) arr.push(
        this[i]); } 
        return arr; }, exists : 
        function(item){ 
        for( 
        var i = 0 ; i < 
        this.
        length ; i++ ){ 
        if( item === 
        this[i]) 
        return 
        true; } 
        return 
        false; }, indexOf : 
        function(item){ 
        for (
        var i = 0; i < 
        this.
        length; i++){ 
        if(
        this[i] === item) 
        return i; } 
        return -1; }, remove : 
        function(item){ 
        var index = 
        this.indexOf(item); 
        if(index != -1){ 
        this.splice(index, 1); } 
        return 
        this; } }; JCore.apply(
        Array.
        prototype,ArrayExtendMethod); 
        /*--------------------------------------------Date对象扩展----------------------------------------*/ 
        var DateExtendMethod ={
        //返回时间间隔(毫秒) getElapsed : 
        function(date) { 
        return 
        Math.abs((date || 
        new 
        Date()).getTime()-
        this.getTime()); } }; JCore.apply(
        Date.
        prototype,DateExtendMethod);