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(email,"Email harus di isi")==false)
  {email.focus();return false;}
  
  if (validate_email(email,"Alamat Email tidak Valid")==false)
    {email.focus();return false;}
  
  if (validate_required(nama,"Nama harus di isi")==false)
  {email.focus();return false;}
  
  if (validate_required(komentar,"Komentar harus di isi")==false)
  {email.focus();return false;}
  }
}

function textCounter(field, countfield, maxlimit) {
	if (field.value.length > maxlimit) // if too long...trim it!
		field.value = field.value.substring(0, maxlimit);
		// otherwise, update 'characters left' counter
	else 
		countfield.value = maxlimit - field.value.length;
}