function Check_Eingabe( theForm )
{
  switch ( theForm.name ) 
  {
    case "Anmelden": 
      {
        if (!CheckField( theForm.strEMail, "E-Mail", "EMail" )) return (false);
        return (CheckOK( theForm.blnEingabe ));
        break;
      }
    case "Abmelden": 
      {
        if (!CheckField( theForm.strEMail, "E-Mail", "EMail" )) return (false);
        return (CheckOK( theForm.blnEingabe ));
        break;
      }
    default: alert("Formular " + theForm.name + " ist nicht definiert"); return (false); break;
  }
}