function checkform()
{
	var my_car=document.form1.sitename.value;
  	var fn = my_car.replace(/^\s+|\s+$/, '');
  	if(fn=='')
  	{
		alert('Please Enter Site  Name !');
		document.form1.sitename.focus();
		return false;
 	 }	
 var my_car=document.form1.site_url.value;
  var fn = my_car.replace(/^\s+|\s+$/, '');
  if(fn=='http://')
  {
	alert('Please Enter Site URL !');
	document.form1.site_url.focus();
	return false;
  }	
  var my_car=document.form1.site_descp.value;
  var fn = my_car.replace(/^\s+|\s+$/, '');
   if (fn=='') 
  {
    alert( "Please Site Description.");
    document.form1.site_descp.focus();
    return false ;
  }
  if(document.form1.url_link.value=='http://')
	{
	   alert("Please Enter URL of Link to us.");
	   document.form1.url_link.focus();
	   return false;
	}
	 var my_car=document.form1.contact_name.value;
  var fn = my_car.replace(/^\s+|\s+$/, '');
  if(fn=='')
  {
	alert('Please Enter Contact Number !');
	document.form1.contact_name.focus();
	return false;
  }	
  if(isNaN(document.form1.contact_name.value))
	{
	   alert("Please Enter Vailid  Contact Number !");
	   document.form1.contact_name.focus();
	   return false;
  }
 
 if(document.form1.email.value=='')
			{
				alert("Please Enter Email Id !");
				document.form1.email.focus();
				return false;
			}
			if(!is_email(document.form1.email.value))
			{
				alert('Please Enter the Correct Email Id!');
				document.form1.email.value=='';
				document.form1.email.focus();
				return false;
			}
	 
}
function is_email(email)
	{
		if(!email.match(/^[A-Za-z0-9\._\-+]+@[A-Za-z0-9_\-+]+(\.[A-Za-z0-9_\-+]+)+$/))
			return false;
		return true;
	}
// End of is_email Function

//  this function checks the given number is signed/unsigned number
//  and return true or false accordingly.
	/*function is_number(number)
	{
		if(!number.match(/^[\-\+0-9e1-9]+$/))
			return false;
		return true;
	}*/