Control.BackgroundImageChanged Control.BackgroundImageChanged Control.BackgroundImageChanged Control.BackgroundImageChanged Event

Definición

Se produce cuando cambia el valor de la propiedad BackgroundImage.Occurs when the value of the BackgroundImage property changes.

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

Ejemplos

El siguiente ejemplo de código es un controlador de eventos que se ejecuta Text cuando cambia el valor de la propiedad.The following code example is an event handler that is executed when the Text property value changes. La Control clase tiene varios métodos con el patrón de nombre PropertyName Changed que se desencadenan cuando cambia el valor de PropertyName correspondiente (PropertyName representa el nombre de la propiedad correspondiente).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).

En el ejemplo de código siguiente ForeColor se cambia TextBox el de un dato de moneda que se muestra.The following code example changes the ForeColor of a TextBox displaying currency data. En el ejemplo se convierte el texto en un número decimal y se ForeColor cambia Color.Red a si el número es negativo y Color.Black a si el número es positivo.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. Este ejemplo requiere que tenga un Form que contenga un. TextBoxThis 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 

Comentarios

Este evento se desencadena si se BackgroundImage cambia la propiedad mediante una modificación mediante programación o una interacción del usuario.This event is raised if the BackgroundImage property is changed by either a programmatic modification or user interaction.

Para obtener más información sobre el manejo de eventos, consulte controlar y provocar eventos.For more information about handling events, see Handling and Raising Events.

Se aplica a

Consulte también: