function formValidation(thisform)
{
with (thisform)
	{
		if (emptyvalidation(firstName,"The 'First name' field is empty.\nPlease check your entry.")==false) {firstName.focus(); return false;};
		if (emptyvalidation(surName,"The 'Surname' is empty.\nPlease check your entry.")==false) {surName.focus(); return false;};
		if (emptyvalidation(jobTitle,"The 'Job Title' field is empty.\nPlease check your entry.")==false) {surName.focus(); return false;};
		if (emptyvalidation(organisation,"The 'organisation' field is empty.\nPlease check your entry.")==false) {surName.focus(); return false;};
		if (emptyvalidation(addressLine1,"'Address Line 1' is empty.\nPlease check your entry.")==false) {surName.focus(); return false;};
		if (emptyvalidation(postCode,"The 'Post Code' field is empty.\nPlease check your entry.")==false) {surName.focus(); return false;};
		if (emptyvalidation(email,"The 'Email address' field is empty.\nPlease check your entry.")==false) {email.focus(); return false;};
		if (emailvalidation(email,"Your email address appears to be illegal.\nPlease check your entry.")==false) {email.focus(); return false;};
		if (emptyvalidation(phoneNo,"The 'Phone number' box is empty.\nPlease check your entry.")==false) {message.focus(); return false;};
		if (numbervalidation(phoneNo,"The phone number contains illegal characters.\nPlease check your entry.")==false) {phoneNo.focus(); return false;};
	}
} 
function emailvalidation(entered, alertbox)
{
	with (entered)
	{
	apos=value.indexOf("@");
	dotpos=value.lastIndexOf(".");
	lastpos=value.length-1;
	if (apos<1 || dotpos-apos<2 || lastpos-dotpos>3 || lastpos-dotpos<2)
	{if (alertbox) {alert(alertbox);} return false;}
	else {return true;}
	}
} 

function emptyvalidation(entered, alertbox)
{
	with (entered)
	{
	if (value==null || value=="")
	{if (alertbox!="") {alert(alertbox);} return false;}
	else {return true;}
	}
}


function numbervalidation(entered, alertbox)
{
	var ValidChars = "-0123456789.() ";
   	var IsNumber=true;
   	var Char;
	with (entered)
	{
	for (i = 0; i < value.length && IsNumber == true; i++) 
      { 
      Char = value.charAt(i); 
      if (ValidChars.indexOf(Char) == -1) 
         {
         if (alertbox!="") {
				alert(alertbox);
				} 
			return false;
         }
      }
    return true;
	}
}