Control.Validating Événement

Définition

Se produit lors de la validation du contrôle.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 

Exemples

L’exemple de code suivant utilise la classe dérivée TextBox et valide une adresse de messagerie entrée par l’utilisateur.The following code example uses the derived class TextBox and validates an email address that the user enters. Si l’adresse de messagerie n’est pas au format standard (contenant « @" and ". »), la validation échoue, une icône de ErrorProvider s’affiche et l’événement est annulé.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. Cet exemple requiert qu’un contrôle TextBox et ErrorProvider aient été créés sur un formulaire.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

Remarques

Lorsque vous modifiez le focus à l’aide du clavier (TAB, MAJ + TAB, etc.), en appelant les méthodes Select ou SelectNextControl, ou en définissant la propriété ContainerControl.ActiveControl sur le formulaire actuel, les événements de focus se produisent dans l’ordre suivant :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

Lorsque vous modifiez le focus à l’aide de la souris ou en appelant la méthode Focus, les événements de focus se produisent dans l’ordre suivant :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

Si la propriété CausesValidation est définie sur false, les événements Validating et Validated sont supprimés.If the CausesValidation property is set to false, the Validating and Validated events are suppressed.

Si la propriété Cancel de la CancelEventArgs est définie sur true dans le délégué d’événement Validating, tous les événements qui se produisent habituellement après l’événement Validating sont supprimés.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.

Attention

N’essayez pas de définir le focus à partir des gestionnaires d’événements Enter, GotFocus, Leave, LostFocus, Validating ou Validated.Do not attempt to set focus from within the Enter, GotFocus, Leave, LostFocus, Validating, or Validated event handlers. Cela peut entraîner l’arrêt de la réponse de votre application ou du système d’exploitation.Doing so can cause your application or the operating system to stop responding. Pour plus d’informations, consultez la rubrique WM_KILLFOCUS de la section « référence d’entrée au clavier » et la section « interblocages de messages » de la rubrique « à propos des messages et des files d’attente de messages » dans MSDN Library à l’adresse https://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 https://msdn.microsoft.com/library.

Pour plus d'informations sur la gestion des événements, voir gestion et déclenchement d’événements.For more information about handling events, see Handling and Raising Events.

S’applique à

Voir aussi