正则表达式

wzwd111

http://www.iteye.com/topic/30728
 
//校验登录名：只能输入5-20个以字母开头、可带数字、“_”、“.”的字串
function isRegisterUserName(s)   
{   
var patrn=/^[a-zA-Z]{1}([a-zA-Z0-9]|[._]){4,19}$/;   
if (!patrn.exec(s)) return false  
return true  
} 
 
http://hi.baidu.com/zhanghy0327/blog/item/1ff10cdf4b7f625e95ee37fa.html
<script type="text/javascript">
                function strValid(){
                        var str = document.getElementById('test').value;
                        //alert(str);
                        //var pattern = /^[A-Za-z]+$/;        //由26个英文字母组成的字符串
                        //var pattern = /^[A-Za-z0-9]+$/;        //由数字和26个英文字母组成的字符串
                        var pattern = /^[\u4e00-\u9fa5A-Za-z0-9_]+$/;        //由1位以上的数字、英文字母、汉字或下划线组成的字符串
                        if(pattern.test(str)){
                                alert("成了");
                        }else{
                                alert("失败了");
                        }
                }
        </script>