js执行时间查看器

效果如图所示:

演示代码:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=gb2312" /> <title>test</title> <script src="http://demo.jb51.net/jslib/other/runtime.js"></script></head> <body> </body> <script> onerror = function() { location.reload(); return true; } Test.run( '内部定义' ); for( var i=0; i<9999; i++ ) { 'xxxx'.replace(/\s/g,''); } Test.stop(); Test.run( '外部定义' ); var reg = /\s/g; for( var i=0; i<9999; i++ ) { 'xxxx'.replace(reg,''); } Test.stop(); Test.run( '使用new' ); for( var i=0; i<9999; i++ ) { 'xxxx'.replace(new RegExp('\\s','g'),''); } Test.stop(); Test.output( '正则表达式性能测试' ); </script></html>
[Ctrl+A 全选 注:如需引入外部Js需刷新才能执行]
文中所用到的runtime.js下载地址