<html> <head> <title></title> </head> <body><script type="text/javascript"> function StringBuffer() ...{ this._strings = []; } StringBuffer.prototype.append = function(str) ...{ this._strings.push(str); } StringBuffer.prototype.toString = function() ...{ return this._strings.join(""); } //实际例子 var buffer = new StringBuffer(); buffer.append("123"); buffer.append("456"); alert(buffer.toString());</script><script type="text/jscript"> //对比运行效率 var d1 = new Date(); var str = ""; for(var i=0; i<10000; i++) ...{ str += "text"; } var d2 = new Date(); document.write("用加好连接;" + (d2.getTime() - d1.getTime()) + "毫秒"); var oBuffer = new StringBuffer(); d1 = new Date(); for(var i=0;i<10000;i++) ...{ oBuffer.append("text"); } var sResult = buffer.toString(); d2 = new Date(); document.write("<br />用StringBuffer连接" + (d2.getTime() - d1.getTime()) + "毫秒");</script> </body></html>