// JavaScript Document
function checkelement(form){	
		
if (form.Name.value == "")
  {
    alert("请在姓名域中输入值。");
    form.Name.focus();
    return (false);
  }

  if (form.Addr.value == "")
  {
    alert("请在通信地址域中输入值。");
    form.Addr.focus();
    return (false);
  }
  if (form.Postcode.value == "")
  {
    alert("请在邮编域中输入值。");
    form.Postcode.focus();
    return (false);
  }
  if (form.Teledistinct.value == "")
  {
    alert("请在电话区号域中输入值。");
    form.Teledistinct.focus();
    return (false);
  }
  if (form.Tele.value == "")
  {
    alert("请在电话号码中输入值。");
    form.Tele.focus();
    return (false);
  }

   if (form.Mobletel.value == "")
  {
    alert("请在手机号码中输入值。");
    form.Mobletel.focus();
    return (false);
  }

    if (form.Sendername.value == "")
  {
    alert("请在Email中输入值。");
    form.Sendername.focus();
    return (false);
  }
    if (form.Sendercom.value == "")
  {
    alert("请在Email中输入值。");
    form.Sendercom.focus();
    return (false);
  }

    if (form.Content.value == "")
  {
    alert("请在内容中输入值。");
    form.Content.focus();
    return (false);
  }

  
		if(!isNumber(form.Postcode.value))
		{
			alert('邮编格式不正确');
			form.Postcode.focus();          		
       		return false;
		}
		
		if(!isNumber(form.Teledistinct.value))
		{
			alert('电话格式不正确');
			form.Teledistinct.focus();          		
       		return false;
		}

		if(!isNumber(form.Tele.value))
		{
			alert('电话格式不正确');
			form.Tele.focus();          		
       		return false;
		}

		
		if(!isNumber(form.Mobletel.value))
		{
			alert('手机格式不正确');
			form.Mobletel.focus();          		
       		return false;
		}

		if(!isEmail(form.Sendercom.value))
		{
			alert('Email格式不正确');
			form.Sendercom.focus();          		
       		return false;
		}
}

function isNumber(s) //数字判断函数
{
var digits = "0123456789";
var i = 0;
var sLength = s.length;

while ((i < sLength))
{
var c = s.charAt(i);
if (digits.indexOf(c) == -1) return false;
i++;
}
return true;
}

function isEmail(s) //邮件判断函数
{
var digits = ".";
var i = 0;
var sLength = s.length;

while ((i < sLength))
{
var c = s.charAt(i);
if (digits.indexOf(c)!=-1) return true;
i++;
}
return false;
}