function checkvalid()
{
	if(validate() == true)
	{
		document.frmcontact.submit();
	}
}

function validate()
{
	var name = document.frmcontact.txtname.value;
	if(name.length < 1)
	{
		alert("Please enter your name");
		document.frmcontact.txtname.focus();
		return false;
	}
	
	var telno = document.frmcontact.txttelno.value;
	if(telno.length < 1)
	{
		alert("Please enter your telephone number");
		document.frmcontact.txttelno.focus();
		return false;
	}
	
	var emailid = document.frmcontact.txtemailid.value;
	if(emailid.length < 1)
	{
		alert("Please enter your email id");
		document.frmcontact.txtemailid.focus();
		return false;
	}
	if(isvalid_email(emailid) == false)
	{
		alert("Please check your email id");
		document.frmcontact.txtemailid.focus();
		return false;		
	}
	return true;
}

var emailfilter=/^\w+[\+\.\w-]*@([\w-]+\.)*\w+[\w-]*\.([a-z]{2,4}|\d+)$/i;

function isvalid_email(str)
{
	return emailfilter.test(str);
}