<SCRIPT LANGUAGE="JavaScript">
<!-- 
function Juge(theForm) 
{ 
if (theForm.username.value == "") 
{
alert("请您输入您的姓名!"); 
theForm.username.focus(); 
return (false); 
}

if (theForm.pwd.value == "") 
{
alert("请您输入您的密码!"); 
theForm.pwd.focus(); 
return (false); 
}

var strDate=theForm.vdate.value;
re=/\d{4}\/\d{2}\/\d{2}/g
if(re.test(strDate))
{
	var DateArray=strDate.split("/");
	var dateElement=new Date(DateArray[0],parseInt(DateArray[1])-1,DateArray[2]);      
	if(!((dateElement.getYear()==parseInt(DateArray[0]))&&((dateElement.getMonth()+1)==parseInt(DateArray[1]))&&(dateElement.getDate()==parseInt(DateArray[2])))) 
	{
		alert("不符合日期逻辑")
		strDate='';
		theForm.vdate.focus(); 
		return (false); 
	}
}
else
{
	alert("日期格式输入错误")
	strDate='';
	theForm.vdate.focus(); 
	return (false); 
}


if(isNaN(theForm.old.value)){
 	alert("请您输入正确而且符合条件的年龄数字");
 	theForm.old.focus();
 	theForm.old.value=""
  	return (false);
}


if (theForm.email.value == "") 
{
alert("请您输入email地址!"); 
theForm.email.focus(); 
return (false); 
}
var checkOK = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_@."; 
var checkStr = theForm.email.value;
var allValid = true; 

for (i = 0; i < checkStr.length; i++)           
{ 
ch = checkStr.charAt(i);                        
for (j = 0; j < checkOK.length; j++)          
if (ch == checkOK.charAt(j))                  
	break;                                
	if (j == checkOK.length)
	{ 
		allValid = false; 
		break;                    
	} 
} 


if (theForm.email.value.length < 6)
{ 
allValid = false; 
} 

if (!allValid) 
{ 
alert("您输入的 \"电子邮件地址\" 无效!"); 
theForm.email.focus(); 
return (false); 
} 

address=theForm.email.value; 
if(address.length>0) 
{ 
i=address.indexOf("@"); 
if(i==-1) 
{ 
alert("对不起！您输入的电子邮件地址是错误的！")
theForm.email.focus();
return false; 
} 
p=address.indexOf(".") 
if(p==-1) 
{ 
alert("对不起！您输入的电子邮件地址是错误的！") 
theForm.email.focus(); 
return false; 
} 
} 

obj=theForm.ip.value      
var exp=/^(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])$/;
var reg = obj.match(exp); 
if(reg==null) 
{ 
alert("IP地址不合法!"); 
theForm.ip.focus(); 
return false; 
} 
} 
//-->
</script> 
<form method="post" onSubmit="return Juge(PostTopic)" name="PostTopic">
&nbsp;&nbsp;姓名:<input type=text name=username size=20><br>
&nbsp;&nbsp;密码:<input type=password name=pwd size=20><br>
&nbsp;&nbsp;日期:<input type=text name=vdate size=20>&nbsp;格式:YYYY/MM/DD<br>
&nbsp;&nbsp;年龄:<input type=text name=old size=5><br>
&nbsp;&nbsp;邮件:<input type=text name=email size=20><br>
IP地址:<input type=text name=ip size=20><br><br>
&nbsp;&nbsp;<input type=submit value=校验 name=b1>

</form>