JavaScript中用正则表达式匹配URL

用JavaScript验证匹配URL是否合法的代码

        var strRegex = "^((https|http|ftp|rtsp|mms)?://)"  
        + "?(([0-9a-z_!~*'().&=+$%-]+: )?[0-9a-z_!~*'().&=+$%-]+@)?" //ftp的user@  
        + "(([0-9]{1,3}\.){3}[0-9]{1,3}" // IP形式的URL- 199.194.52.184  
        + "|" // 允许IP和DOMAIN（域名） 
        + "([0-9a-z_!~*'()-]+\.)*" // 域名- www.  
        + "([0-9a-z][0-9a-z-]{0,61})?[0-9a-z]\." // 二级域名  
        + "[a-z]{2,6})" // first level domain- .com or .museum  
        + "(:[0-9]{1,4})?" // 端口- :80  
        + "((/?)|" // a slash isn't required if there is no file name  
        + "(/[0-9a-z_!~*'().;?:@&=+$,%#-]+)+/?)$";