function validate_required(field,alerttxt)
{
with (field)
  {
  if (value==null||value=="")
    {
    alert(alerttxt);return false;
    }
  else
    {
    return true;
    }
  }
}


function validate_email(field,alerttxt)
{
with (field)
  {
  apos=value.indexOf("@");
  dotpos=value.lastIndexOf(".");
  if (apos<1||dotpos-apos<2)
    {alert(alerttxt);return false;}
  else {return true;}
  }
}



function validate_form(thisform)
{
with (thisform)
  {
  
  if (validate_required(Name,"Name must be filled in")==false)
  {Name.focus();return false;}
  }
 
 with (thisform)
  {
  
  if (validate_required(Cell,"Cell number must be filled in")==false)
  {Cell.focus();return false;}
  }
  
  
  with (thisform)
  {
  
  if (validate_email(Email,"Please fill in a correct email address")==false)
  {Email.focus();return false;}
  }
  
 
}