<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <title>chat.html</title> <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"> <meta http-equiv="description" content="this is my page"> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> <!--<link rel="stylesheet" type="text/css" href="./styles.css">--> <script type="text/javascript"> //定义id抽取函数.....目前只能抽取ID var $=function(id){ return document.getElementById(id); }; //定义javascript对象:java类 function FuncObj(name, job, born){ this.name = name; this.job = job; this.born = born; function fn2(){ alert(this.new); }; new_it:"i am new push by FcunObj fn2"; }; //在函数原型操作类:java——对类的操作与方法进行修改 FuncObj.prototype.fn=function(){ alert("fn"); }; function showColor() { alert(this.color); }; function click_(){ showColor(); //跟Java也太像了吧~ new FuncObj().fn(); var obj2 = new FuncObj(); alert(obj2.fn2); alert(obj2.new_it); // obj2.fn2(); alert(FuncObj.toString()); alert(FuncObj.prototype.fn.toString()); alert("enter click"); alert($("fst_div")); }; </script> </head> <body> <div id="fst_div" ></div> <button onclick="click_();">______</button> <div></div> <div></div> </body> </html>
/**javascript 模拟 StringBuffer();*/ function StringBuffer () { this._strings_ = new Array(); } StringBuffer.prototype.append = function(str) { this._strings_.push(str); }; StringBuffer.prototype.toString = function() { return this._strings_.join(""); }; sb.append("123"); sb.append("456"); document.write(sb.toString()); /**测试性能,跟预期结果相反*/ var d1 = new Date(); var str = ""; for (var i=0; i < 10000; i++) { str += "text"; } var d2 = new Date(); document.write("Concatenation with plus: " + (d2.getTime() - d1.getTime()) + " milliseconds"); var buffer = new StringBuffer(); d1 = new Date(); for (var i=0; i < 10000; i++) { buffer.append("text"); } var result = buffer.toString(); d2 = new Date(); document.write("<br />Concatenation with StringBuffer: " + (d2.getTime() - d1.getTime()) + " milliseconds");