ConvertEventHandler ConvertEventHandler ConvertEventHandler ConvertEventHandler Delegate

定義

ParseFormat イベントおよび Binding イベントを処理するメソッドを表します。Represents the method that will handle the Parse and Format events of a Binding.

public delegate void ConvertEventHandler(System::Object ^ sender, ConvertEventArgs ^ e);
public delegate void ConvertEventHandler(object sender, ConvertEventArgs e);
type ConvertEventHandler = delegate of obj * ConvertEventArgs -> unit
Public Delegate Sub ConvertEventHandler(sender As Object, e As ConvertEventArgs)

パラメーター

sender
Object Object Object Object

イベントのソース。The source of the event.

e
ConvertEventArgs ConvertEventArgs ConvertEventArgs ConvertEventArgs

イベント データを格納している ConvertEventArgsA ConvertEventArgs that contains the event data.

継承
ConvertEventHandlerConvertEventHandlerConvertEventHandlerConvertEventHandler

次のコードThe following code

例を作成します、Bindingを追加します、ConvertEventHandler両方へのデリゲート、ParseFormatイベント、し、追加、BindingBindingsCollectionTextBoxを介して制御、DataBindingsプロパティ。example creates a Binding, adds a ConvertEventHandler delegate to both the Parse and Format events, and adds the Binding to the BindingsCollection of a TextBox control through the DataBindings property. DecimalToCurrencyに追加のイベントのデリゲート、Formatイベント、バインドされた値の書式設定 (、Decimal型) の通貨を使用して、ToStringメソッド。The DecimalToCurrency event delegate, added to the Format event, formats the bound value (a Decimal type) as currency using the ToString method. CurrencyToDecimalに追加のイベントのデリゲート、Parseイベントをコントロールに表示される値の変換に、Decimal型。The CurrencyToDecimal event delegate, added to the Parse event, converts the value displayed by the control back to the Decimal type.

private:
   void DecimalToCurrency( Object^ /*sender*/, ConvertEventArgs^ cevent )
   {
      // The method converts only to string type. Test this using the DesiredType.
      if ( cevent->DesiredType != String::typeid )
      {
         return;
      }
      
      // Use the ToString method to format the value as currency ("c").
      cevent->Value = ( (Decimal^)(cevent->Value) )->ToString( "c" );
   }

   void CurrencyToDecimal( Object^ /*sender*/, ConvertEventArgs^ cevent )
   {
      // ' The method converts only to decimal type. 
      if ( cevent->DesiredType != Decimal::typeid )
      {
         return;
      }

      // Converts the string back to decimal using the static ToDecimal method.
      cevent->Value = Convert::ToDecimal( cevent->Value->ToString() );
   }

   void BindControl()
   {
      // Creates the binding first. The OrderAmount is typed as Decimal.
      Binding^ b = gcnew Binding(
         "Text",ds,"customers.custToOrders.OrderAmount" );
      
      // Add the delegates to the events.
      b->Format += gcnew ConvertEventHandler(
         this, &Form1::DecimalToCurrency );
      b->Parse += gcnew ConvertEventHandler(
         this, &Form1::CurrencyToDecimal );
      text1->DataBindings->Add( b );
   }
private void DecimalToCurrency(object sender, ConvertEventArgs cevent)
{
   // The method converts only to string type. Test this using the DesiredType.
   if (cevent.DesiredType != typeof(string)) return;

   // Use the ToString method to format the value as currency ("c").
   cevent.Value = ((decimal) cevent.Value).ToString("c");
}

private void CurrencyToDecimal(object sender, ConvertEventArgs cevent)
{
   // ' The method converts only to decimal type. 
   if (cevent.DesiredType != typeof(decimal)) return;

   // Converts the string back to decimal using the static ToDecimal method.
   cevent.Value = Convert.ToDecimal(cevent.Value.ToString());
}

private void BindControl()
{
   // Creates the binding first. The OrderAmount is typed as Decimal.
   Binding b = new Binding
      ("Text", ds, "customers.custToOrders.OrderAmount");
   // Add the delegates to the events.
   b.Format += new ConvertEventHandler(DecimalToCurrency);
   b.Parse += new ConvertEventHandler(CurrencyToDecimal);
   text1.DataBindings.Add(b);
}

Private Sub DecimalToCurrency(sender As Object, cevent As ConvertEventArgs)
    ' The method converts only to string type. Test this using the DesiredType.
    If cevent.DesiredType IsNot GetType(String) Then
        Return
    End If 
    ' Use the ToString method to format the value as currency ("c").
    cevent.Value = CDec(cevent.Value).ToString("c")
End Sub 


Private Sub CurrencyToDecimal(sender As Object, cevent As ConvertEventArgs)
    ' The method converts only to decimal type. 
    If cevent.DesiredType IsNot GetType(Decimal) Then
        Return
    End If 
    ' Converts the string back to decimal using the static ToDecimal method.
    cevent.Value = Convert.ToDecimal(cevent.Value.ToString())
End Sub 


Private Sub BindControl()
    ' Creates the binding first. The OrderAmount is typed as Decimal.
    Dim b As New Binding("Text", ds, "customers.custToOrders.OrderAmount")
    ' Adds the delegates to the events.
    AddHandler b.Format, AddressOf DecimalToCurrency
    AddHandler b.Parse, AddressOf CurrencyToDecimal
    text1.DataBindings.Add(b)
End Sub 

注釈

ConvertEventHandler デリゲートを作成する場合は、イベントを処理するメソッドを指定します。When you create a ConvertEventHandler delegate, you identify the method that will handle the event. イベントをイベント ハンドラーに関連付けるには、デリゲートのインスタンスをイベントに追加します。To associate the event with your event handler, add an instance of the delegate to the event. デリゲートを削除しない限り、そのイベントが発生すると常にイベント ハンドラーが呼び出されます。The event handler is called whenever the event occurs, unless you remove the delegate. イベント ハンドラー デリゲートの詳細については、次を参照してください。処理とイベントの発生します。For more information about event-handler delegates, see Handling and Raising Events.

Extension Methods

GetMethodInfo(Delegate) GetMethodInfo(Delegate) GetMethodInfo(Delegate) GetMethodInfo(Delegate)

指定したデリゲートによって表されるメソッドを表すオブジェクトを取得します。Gets an object that represents the method represented by the specified delegate.

適用対象