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Control.BackgroundImageChanged Event

Occurs when the value of the BackgroundImage property changes.

Namespace:  System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

public event EventHandler BackgroundImageChanged

This event is raised if the BackgroundImage property is changed by either a programmatic modification or user interaction.

For more information about handling events, see Handling and Raising Events.

The following code example is an event handler that is executed when the Text property value changes. The Control class has several methods with the name pattern PropertyName Changed that are raised when the corresponding PropertyName value changes (PropertyName represents the name of the corresponding property).

The following code example changes the ForeColor of a TextBox displaying currency data. 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. 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
   {
      // If there is an error, display the text using the system colors.
      currencyTextBox.ForeColor = SystemColors.ControlText;
   }
}

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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