Control.Validating Control.Validating Control.Validating Control.Validating Event

Definition

Tritt ein, wenn das Steuerelement eine Validierung ausführt.Occurs when the control is validating.

public:
 event System::ComponentModel::CancelEventHandler ^ Validating;
public event System.ComponentModel.CancelEventHandler Validating;
member this.Validating : System.ComponentModel.CancelEventHandler 
Public Custom Event Validating As CancelEventHandler 

Beispiele

Im folgenden Codebeispiel wird verwendet, die abgeleitete Klasse TextBox und überprüft eine e-Mail-Adresse, die der Benutzer eingibt.The following code example uses the derived class TextBox and validates an email address that the user enters. Wenn die e-Mail-Adresse nicht in das Standardformat ist (mit "@" and "."), die Validierung fehlschlägt, eine ErrorProvider Symbol angezeigt wird, und das Ereignis abgebrochen wird.If the email address is not in the standard format (containing "@" and "."), the validation fails, an ErrorProvider icon is displayed, and the event is canceled. In diesem Beispiel erfordert, dass eine TextBox und ErrorProvider Steuerelement in einem Formular erstellt wurden.This example requires that a TextBox and ErrorProvider control have been created on a form.

private:
   void textBox1_Validating( Object^ sender, System::ComponentModel::CancelEventArgs^ e )
   {
      String^ errorMsg;
      if ( !ValidEmailAddress( textBox1->Text, &errorMsg ) )
      {
         // Cancel the event and select the text to be corrected by the user.
         e->Cancel = true;
         textBox1->Select( 0, textBox1->Text->Length );
         
         // Set the ErrorProvider error with the text to display.
         this->errorProvider1->SetError( textBox1, errorMsg );
      }
   }

   void textBox1_Validated( Object^ sender, System::EventArgs^ e )
   {
      // If all conditions have been met, clear the ErrorProvider of errors.
      errorProvider1->SetError( textBox1, "" );
   }

public:
   bool ValidEmailAddress( String^ emailAddress, [Out]interior_ptr<String^> errorMessage )
   {
      // Confirm that the email address String* is not empty.
      if ( emailAddress->Length == 0 )
      {
         *errorMessage = "email address is required.";
         return false;
      }

      // Confirm that there is an "@" and a "." in the email address, and in the correct order.
      if ( emailAddress->IndexOf( "@" ) > -1 )
      {
         if ( emailAddress->IndexOf( ".", emailAddress->IndexOf( "@" ) ) > emailAddress->IndexOf( "@" ) )
         {
            *errorMessage = "";
            return true;
         }
      }

      *errorMessage = "email address must be valid email address format.\n" +
         "For example 'someone@example.com' ";
      return false;
   }
private void textBox1_Validating(object sender, 
 				System.ComponentModel.CancelEventArgs e)
{
   string errorMsg;
   if(!ValidEmailAddress(textBox1.Text, out errorMsg))
   {
      // Cancel the event and select the text to be corrected by the user.
      e.Cancel = true;
      textBox1.Select(0, textBox1.Text.Length);

      // Set the ErrorProvider error with the text to display. 
      this.errorProvider1.SetError(textBox1, errorMsg);
   }
}

private void textBox1_Validated(object sender, System.EventArgs e)
{
   // If all conditions have been met, clear the ErrorProvider of errors.
   errorProvider1.SetError(textBox1, "");
}
public bool ValidEmailAddress(string emailAddress, out string errorMessage)
{
   // Confirm that the email address string is not empty.
   if(emailAddress.Length == 0)
   {
      errorMessage = "email address is required.";
         return false;
   }

   // Confirm that there is an "@" and a "." in the email address, and in the correct order.
   if(emailAddress.IndexOf("@") > -1)
   {
      if(emailAddress.IndexOf(".", emailAddress.IndexOf("@") ) > emailAddress.IndexOf("@") )
      {
         errorMessage = "";
         return true;
      }
   }
   
   errorMessage = "email address must be valid email address format.\n" +
      "For example 'someone@example.com' ";
      return false;
}
   Private Function ValidEmailAddress(ByVal emailAddress As String, ByRef errorMessage As String) As Boolean
      ' Confirm there is text in the control.
      If textBox1.Text.Length = 0 Then
         errorMessage = "Email address is required."
         Return False

      End If

      ' Confirm that there is an "@" and a "." in the email address, and in the correct order.
      If emailAddress.IndexOf("@") > -1 Then
         If (emailAddress.IndexOf(".", emailAddress.IndexOf("@")) > emailAddress.IndexOf("@")) Then
            errorMessage = ""
            Return True
         End If
      End If

      errorMessage = "Email address must be valid email address format." + ControlChars.Cr + _
        "For example 'someone@example.com' "
      Return False
End Function

   Private Sub textBox1_Validating(ByVal sender As Object, _
   ByVal e As System.ComponentModel.CancelEventArgs) Handles textBox1.Validating

      Dim errorMsg As String
      If Not ValidEmailAddress(textBox1.Text, errorMsg) Then
         ' Cancel the event and select the text to be corrected by the user.
         e.Cancel = True
         textBox1.Select(0, textBox1.Text.Length)

         ' Set the ErrorProvider error with the text to display. 
         Me.errorProvider1.SetError(textBox1, errorMsg)
      End If
   End Sub


   Private Sub textBox1_Validated(ByVal sender As Object, _
   ByVal e As System.EventArgs) Handles textBox1.Validated
      ' If all conditions have been met, clear the error provider of errors.
      errorProvider1.SetError(textBox1, "")
   End Sub

Hinweise

Wenn Sie den Fokus ändern, indem Sie mit der Tastatur (Registerkarte, UMSCHALT + TAB, usw.), durch den Aufruf der Select oder SelectNextControl Methoden oder durch Festlegen der ContainerControl.ActiveControl Eigenschaft mit dem aktuellen Formular den Fokusereignisse auftreten, in der folgenden Reihenfolge:When you change the focus by using the keyboard (TAB, SHIFT+TAB, and so on), by calling the Select or SelectNextControl methods, or by setting the ContainerControl.ActiveControl property to the current form, focus events occur in the following order:

  1. Enter

  2. GotFocus

  3. Leave

  4. Validating

  5. Validated

  6. LostFocus

Wenn Sie den Fokus ändern, mit der Maus oder durch Aufrufen der Focus -Methode, den Fokusereignisse auftreten, in der folgenden Reihenfolge:When you change the focus by using the mouse or by calling the Focus method, focus events occur in the following order:

  1. Enter

  2. GotFocus

  3. LostFocus

  4. Leave

  5. Validating

  6. Validated

Wenn die CausesValidation -Eigenschaftensatz auf false, Validating und Validated Ereignisse unterdrückt werden.If the CausesValidation property is set to false, the Validating and Validated events are suppressed.

Wenn die Cancel Eigenschaft der CancelEventArgs nastaven NA hodnotu true in die Validating Ereignisdelegaten, der alle Ereignisse, die in der Regel nach dem auftreten würden die Validating Ereignis werden unterdrückt.If the Cancel property of the CancelEventArgs is set to true in the Validating event delegate, all events that would usually occur after the Validating event are suppressed.

Achtung

Versuchen Sie nicht, legen Sie den Fokus aus dem Enter, GotFocus, Leave, LostFocus, Validating, oder Validated -Ereignishandler.Do not attempt to set focus from within the Enter, GotFocus, Leave, LostFocus, Validating, or Validated event handlers. Auf diese Weise kann dazu führen, dass Ihre Anwendung oder das Betriebssystem nicht mehr reagiert.Doing so can cause your application or the operating system to stop responding. Weitere Informationen finden Sie unter den WM_KILLFOCUS Thema im Abschnitt "Keyboard Input Reference", und im Abschnitt "Message Deadlocks" des Themas "Über Nachrichten und Nachrichtenwarteschlangen" in der MSDN Library unter http://msdn.microsoft.com/library.For more information, see the WM_KILLFOCUS topic in the "Keyboard Input Reference" section, and the "Message Deadlocks" section of the "About Messages and Message Queues" topic in the MSDN library at http://msdn.microsoft.com/library.

Weitere Informationen zur Behandlung von Ereignissen finden Sie unter behandeln und Auslösen von Ereignissen.For more information about handling events, see Handling and Raising Events.

Gilt für:

Siehe auch