Control.RightToLeftChanged 事件

定義

發生在 RightToLeft 屬性值變更時。Occurs when the RightToLeft property value changes.

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

範例

下列程式碼範例是當 Text 屬性值變更時,所執行的事件處理常式。The following code example is an event handler that is executed when the Text property value changes. Control 類別有數個方法,其名稱模式propertynameChanged 會在對應的propertyname值變更時引發(propertyname代表對應屬性的名稱)。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).

下列程式碼範例會變更 TextBoxForeColor,其中顯示貨幣資料。The following code example changes the ForeColor of a TextBox displaying currency data. 此範例會將文字轉換成十進位數,如果數位為負數,則會將 ForeColor 變更為 Color.Red,如果數位是正數,則會 Color.BlackThe 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. 這個範例需要您擁有包含 TextBoxFormThis 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 

備註

如果 RightToLeft 屬性是以程式設計方式修改或使用者互動來變更,就會引發這個事件。This event is raised if the RightToLeft property is changed by either a programmatic modification or user interaction.

如需處理事件的詳細資訊,請參閱處理和引發事件For more information about handling events, see Handling and Raising Events.

適用於

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