// Check the empty fields
function checkField()
{
  var a=document.form1.firstname.value
  var b=document.form1.tel.value
  var c=document.form1.mail.value
  var d=document.form1.comments.value
  
  // check for firstname
  if (a=='')
  {
    alert ('Please enter your First name.')
	return false
	document.form1.firstname.focus()
  }
  
  // check for telephone
  if (b=='')
  {
    alert ('Please enter your Telephone number.')
	return false
	document.form1.tel.focus()
  }
  
  // check for email
  if (c=='')
  {
    alert ('Please enter your Email.')
	return false
	document.form1.mail.focus()
  }
  
  // check for comments
  if (d=='')
  {
    alert ('Please enter your Comments.')
	return false
	document.form1.comments.focus()
  }
}

// Email Validation
function echeck(str) {

		var at="@"
		var dot="."
		var lat=str.indexOf(at)
		var lstr=str.length
		var ldot=str.indexOf(dot)
		if (str.indexOf(at)==-1){
		   alert("Invalid E-mail ID")
		   return false
		}

		if (str.indexOf(at)==-1 || str.indexOf(at)==0 || str.indexOf(at)==lstr){
		   alert("Invalid E-mail ID")
		   return false
		}

		if (str.indexOf(dot)==-1 || str.indexOf(dot)==0 || str.indexOf(dot)==lstr){
		    alert("Invalid E-mail ID")
		    return false
		}

		 if (str.indexOf(at,(lat+1))!=-1){
		    alert("Invalid E-mail ID")
		    return false
		 }

		 if (str.substring(lat-1,lat)==dot || str.substring(lat+1,lat+2)==dot){
		    alert("Invalid E-mail ID")
		    return false
		 }

		 if (str.indexOf(dot,(lat+2))==-1){
		    alert("Invalid E-mail ID")
		    return false
		 }
		
		 if (str.indexOf(" ")!=-1){
		    alert("Invalid E-mail ID")
		    return false
		 }

 		 return true					
	}

function ValidateForm()
{
	var emailID=document.form1.mail
	
	if ((emailID.value==null)||(emailID.value==""))
	{
		alert("Please Enter your Email ID")
		emailID.focus()
		return false
	}
	if (echeck(emailID.value)==false)
	{
		emailID.value=""
		emailID.focus()
		return false
	}
	return true
 }