function validate_form()
{
	var a=document.form1.username.value;
	var b=document.form1.ph_no.value;
	

	if(a=='')
	{
		alert('Enter your name');
		document.form1.username.focus();
		return false;		
	}


	if (b=="")
	{
		alert( 'please enter Phone No.');
		document.form1.ph_no.focus();
		return false;
	}
	if (isNaN(b))
	{
		alert( 'please enter a number');
		document.form1.ph_no.focus();
		return false;
	} 

	}