Control.BackColorChanged Control.BackColorChanged Control.BackColorChanged Control.BackColorChanged Event

Definition

Tritt auf, wenn sich der Wert der BackColor-Eigenschaft ändert.Occurs when the value of the BackColor property changes.

public:
 event EventHandler ^ BackColorChanged;
public event EventHandler BackColorChanged;
member this.BackColorChanged : EventHandler 
Public Custom Event BackColorChanged As EventHandler 

Beispiele

Im folgenden Codebeispiel wird ein Ereignishandler, der ausgeführt wird, wenn die Text Eigenschaftswert ändert.The following code example is an event handler that is executed when the Text property value changes. Die Control -Klasse verfügt über mehrere Methoden mit dem Namensmuster PropertyName Changed sind wird ausgelöst, wenn die entsprechende PropertyName -Wert ändert ( PropertyName stellt den Namen der entsprechenden Eigenschaft dar).The Control class has several methods with the name pattern PropertyNameChanged that are raised when the corresponding PropertyName value changes (PropertyName represents the name of the corresponding property).

Der folgende code Beispiel ändert die ForeColor von eine TextBox Währungsdaten.The following code example changes the ForeColor of a TextBox displaying currency data. Im Beispiel konvertiert den Text in eine Dezimalzahl und Änderungen der ForeColor zu Color.Red , wenn die Zahl negativ ist, und um Color.Black , wenn die Zahl positiv ist.The example converts the text to a decimal number and changes the ForeColor to Color.Red if the number is negative and to Color.Black if the number is positive. In diesem Beispiel benötigen Sie eine Form , enthält eine TextBox.This example requires that you have a Form that contains a TextBox.

private:
   void currencyTextBox_TextChanged( Object^ /*sender*/, EventArgs^ /*e*/ )
   {
      try
      {
         // Convert the text to a Double and determine if it is a negative number.
         if ( Double::Parse( currencyTextBox->Text ) < 0 )
         {
            // If the number is negative, display it in Red.
            currencyTextBox->ForeColor = Color::Red;
         }
         else
         {
            // If the number is not negative, display it in Black.
            currencyTextBox->ForeColor = Color::Black;
         }
      }
      catch ( Exception^ ) 
      {
         // If there is an error, display the text using the system colors.
         currencyTextBox->ForeColor = SystemColors::ControlText;
      }
   }
private void currencyTextBox_TextChanged(object sender, EventArgs e)
{
   try
   {
      // Convert the text to a Double and determine if it is a negative number.
      if(double.Parse(currencyTextBox.Text) < 0)
      {
         // If the number is negative, display it in Red.
         currencyTextBox.ForeColor = Color.Red;
      }
      else
      {
         // If the number is not negative, display it in Black.
         currencyTextBox.ForeColor = Color.Black;
      }
   }
   catch
   {
      // If there is an error, display the text using the system colors.
      currencyTextBox.ForeColor = SystemColors.ControlText;
   }
}
Private Sub currencyTextBox_TextChanged(sender As Object, _ 
  e As EventArgs) Handles currencyTextBox.TextChanged
   Try
      ' Convert the text to a Double and determine if it is a negative number.
      If Double.Parse(currencyTextBox.Text) < 0 Then
         ' If the number is negative, display it in Red.
         currencyTextBox.ForeColor = Color.Red
      Else
         ' If the number is not negative, display it in Black.
         currencyTextBox.ForeColor = Color.Black
      End If
   Catch
      ' If there is an error, display the text using the system colors.
      currencyTextBox.ForeColor = SystemColors.ControlText
   End Try
End Sub 

Hinweise

Dieses Ereignis wird ausgelöst, wenn die BackColor -Eigenschaft entweder durch eine programmgesteuerte Änderung oder Benutzerinteraktion geändert wird.This event is raised if the BackColor property is changed by either a programmatic modification or user interaction.

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