function checkform()
{
	if(document.getElementById("name").value=="")
	{
		alert("name!");
		ask.name.focus();
		return false;
	}
	
	if(document.getElementById("national").value=="")
	{
		alert("national!");
		ask.national.focus();
		return false;
	}
	
	if(document.getElementById("company").value=="")
	{
		alert("company!");
		ask.company.focus();
		return false;
	}
	
	
	if(document.getElementById("telephone").value=="")
	{
		
		alert("telephone!");
		ask.telephone.focus();
		return false;
	}
	if(isTel(document.getElementById("telephone").value))
	{
		
		alert("telephone!");
		ask.telephone.focus();
		return false;
	}
	
	if(document.getElementById("email").value=="")
	{
		alert("email!");
		ask.email.focus();
		return false;
	}
	
	if(!document.getElementById("email").value=="")
	{
		if(isMail(document.getElementById("email").value))
	    {
		alert("E-MAIL!");
		ask.email.focus();
		return false;
	    }	
	}
	
	if(document.getElementById("otherpwd").value=="")
	{
		alert("Please input the Verification code!");
		ask.otherpwd.focus();
		return false;
	}
	
	

}
	







//校验是否全由数字组成 
function isDigit(s) 
{ 
var patrn=/^[0-9]{1,20}$/; 
if (patrn.exec(s)) return false 
return true 
} 

//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 
} 

//校验用户姓名：只能输入1-30个以字母开头的字串 
function isTrueName(s) 
{ 
var patrn=/^[a-zA-Z]{1,30}$/; 
if (patrn.exec(s)) return false 
return true 
} 

//校验密码：只能输入6-20个字母、数字、下划线 
function isPasswd(s) 
{ 
var patrn=/^(\w){6,20}$/; 
if (patrn.exec(s)) return false 
return true 
} 

//校验普通电话、传真号码：可以“+”开头，除数字外，可含有“-” 
function isTel(s) 
{ 
//var patrn=/^[+]{0,1}(\d){1,3}[ ]?([-]?(\d){1,12})+$/; 
var patrn=/^[+]{0,1}(\d){1,3}[ ]?([-]?((\d)|[ ]){1,12})+$/; 
if (patrn.exec(s)) return false 
return true 
} 

//校验手机号码：必须以数字开头，除数字外，可含有“-” 
function isMobil(s) 
{ 
var patrn=/^[+]{0,1}(\d){1,3}[ ]?([-]?((\d)|[ ]){1,12})+$/; 
if (patrn.exec(s)) return false 
return true 
} 

//校验邮政编码 
function isPostalCode(s) 
{ 
//var patrn=/^[a-zA-Z0-9]{3,12}$/; 
var patrn=/^[a-zA-Z0-9 ]{3,12}$/; 
if (patrn.exec(s)) return false 
return true 
} 
//校验QQ 
function isQQ(s) 
{ 
//var patrn=/^[a-zA-Z0-9]{3,12}$/; 
var patrn=/[1-9][0-9]{4,}/; 
if (patrn.exec(s)) return false 
return true 
} 

//校验邮件 
function isMail(s) 
{ 
//var patrn=/^[a-zA-Z0-9]{3,12}$/; 
var patrn=/\w+([-+.]\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*/; 
if (patrn.exec(s)) return false 
return true 
}