function cancel()
{
	mail.reset();
}


function checkinput()
{
	var Letters = "ABCDEFGHIJKLMNOPQRSTUVWXYZ_-.1234567890"
	for (i=0; i < document.mail.username.value.length; i++)
		{
			var CheckChar = document.mail.username.value.charAt(i);
			CheckChar = CheckChar.toUpperCase();
			if (Letters.indexOf(CheckChar) == -1)
			{
			alert ("用户名中有非法字符或格！");
			return false;
					}
					}
		if(mail.username.value.length<1)
		{		alert("请输入用户名！");
		return false;}


		var Letters = "ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890"
	for (i=0; i < document.mail.passwd.value.length; i++)
		{
			var CheckChar = document.mail.passwd.value.charAt(i);
			CheckChar = CheckChar.toUpperCase();
			if (Letters.indexOf(CheckChar) == -1)
			{
			alert ("密码只能由数字和字母组合，并不能空格！");
			return false;
					}
					}
		if(mail.passwd.value.length<6)
		{alert("密码长度不足6位！");
		return false;}
	
	
	
//		mail.submit()
}