function validateform()
{	
	var err = "";
	
	if (document.feedbackForm.ddl_country.value == 'NIL')
	{
		err = "请输入您来自的国家。<br>";
	}
	if (document.feedbackForm.txt_Name.value == '')
	{
		err = err + "请输入您的姓名。<br>"
	}
	if (document.feedbackForm.txt_Email.value == '')
	{
		err = err + "请输入您的电邮地址。<br>"		
	}
	else
	{
		var at="@";
		var dot=".";
		var temp_str = document.feedbackForm.txt_Email.value;
		var lstr=temp_str.length
		var lat=temp_str.indexOf(at)		
		var ldot=temp_str.indexOf(dot)
		if (lat == -1 || lat == 0 || ldot == -1 || ldot == 0)
		{
			err = err + "请输入正确的电邮地址。<br>"
		}		
	}	

	//spam tracker : Start
	if (document.feedbackForm.txta_Comments.value != '')
	{
		var str  = document.feedbackForm.txta_Comments.value
		if ((str.indexOf("http://") > -1)||(str.indexOf("www.") > -1)||(str.indexOf("http") > -1)||(str.indexOf("ftp") > -1))
		{			
			err = err + "请输入完整的询问，网站连结不被接受，谢谢。<br>"
		}
	}
	//spam tracker : End

	if (err == "")
	{
		document.feedbackForm.submit();
	}
	else
	{
		document.getElementById("errcheck").innerHTML = "<font color='red' size='2'><u>错误</u><br>" + err + "</font>";
		window.location.href="#top";
	}
}