function check_input()
{  
	if (mywebmail.gs.value=="")
	{	alert("Please enter your company name");
		mywebmail.gs.focus();
		return false;
	}
    if (mywebmail.name.value=="" )
	{	alert("Please enter your contact name");
		mywebmail.name.focus();
		return false;
	}
	if (mywebmail.email.value=="")
	{	alert("Please enter your email address correctly");
		mywebmail.email.focus();
		return false;
	}
	if (mywebmail.bz.value=="")
	{	alert("Please tell us your request or question");
		mywebmail.bz.focus();
		return false;
	}
  var regu = "^(([0-9a-zA-Z]+)|([0-9a-zA-Z]+[_.0-9a-zA-Z-]*[0-9a-zA-Z]+))@([a-zA-Z0-9-]+[.])+([a-zA-Z]{2}|net|NET|com|COM|gov|GOV|mil|MIL|org|ORG|edu|EDU|int|INT)$"
         var re = new RegExp(regu);

	//Êý×ÖÅжϺ¯Êý
        function isNumber(s) //Êý×ÖÅжϺ¯Êý
        {
                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;
			}
}