Binding.Parse Binding.Parse Binding.Parse Binding.Parse Event

定義

データ連結コントロールの値が変更されると発生します。Occurs when the value of a data-bound control changes.

public:
 event System::Windows::Forms::ConvertEventHandler ^ Parse;
public event System.Windows.Forms.ConvertEventHandler Parse;
member this.Parse : System.Windows.Forms.ConvertEventHandler 
Public Custom Event Parse As ConvertEventHandler 

次のコード例ではBinding、を作成ConvertEventHandlerし、イベントBindingsCollectionParse Formatイベントの両方にデリゲートをBinding追加し、をTextBox使用してDataBindings 、コントロールのにを追加します。".The following code 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. イベントDecimalToCurrencyString Decimalに追加されたイベントデリゲートは、 ToStringメソッドを使用して、バインドされた値 (型) を通貨として書式設定します。 FormatThe DecimalToCurrencyString event delegate, added to the Format event, formats the bound value (a Decimal type) as currency using the ToString method. イベントCurrencyStringToDecimal Decimalに追加されたイベントデリゲートは、コントロールによって表示される値を型に変換します。 ParseThe CurrencyStringToDecimal event delegate, added to the Parse event, converts the value displayed by the control back to the Decimal type.

private:
   void DecimalToCurrencyString( 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 CurrencyStringToDecimal( Object^ /*sender*/, ConvertEventArgs^ cevent )
   {
      // The method converts back to decimal type only.
      if ( cevent->DesiredType != Decimal::typeid )
      {
         return;
      }
      
      // Converts the string back to decimal using the static Parse method.
      cevent->Value = Decimal::Parse( cevent->Value->ToString(),
         NumberStyles::Currency, nullptr );
   }

   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 event.
      b->Format += gcnew ConvertEventHandler( this, &Form1::DecimalToCurrencyString );
      b->Parse += gcnew ConvertEventHandler( this, &Form1::CurrencyStringToDecimal );
      text1->DataBindings->Add( b );
   }
private void DecimalToCurrencyString(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 CurrencyStringToDecimal(object sender, ConvertEventArgs cevent)
{
   // The method converts back to decimal type only.
   if(cevent.DesiredType != typeof(decimal)) return;

   // Converts the string back to decimal using the static Parse method.
   cevent.Value = Decimal.Parse(cevent.Value.ToString(),
   NumberStyles.Currency, null);
}

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 event.
   b.Format += new ConvertEventHandler(DecimalToCurrencyString);
   b.Parse += new ConvertEventHandler(CurrencyStringToDecimal);
   text1.DataBindings.Add(b);
}

Private Sub DecimalToCurrencyString(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
        Exit Sub
    End If
    
    ' Use the ToString method to format the value as currency ("c").
    cevent.Value = CType(cevent.Value, decimal).ToString("c")
End Sub

Private Sub CurrencyStringToDecimal(sender As Object, cevent As ConvertEventArgs)
    ' The method converts back to decimal type only.
    If cevent.DesiredType IsNot GetType(Decimal) Then
        Exit Sub
    End If

    ' Convert the string back to decimal using the shared Parse method.
   cevent.Value = Decimal.Parse(cevent.Value.ToString, _
  NumberStyles.Currency, nothing)

End Sub

Private Sub BindControl
    ' Create the binding first. The OrderAmount is typed as Decimal.
    Dim b As Binding = New Binding _
        ("Text", ds, "Customers.custToOrders.OrderAmount")
    ' Add the delegates to the event.
    AddHandler b.Format, AddressOf DecimalToCurrencyString
    AddHandler b.Parse, AddressOf CurrencyStringToDecimal
    text1.DataBindings.Add(b)
End Sub

注釈

イベントFormatParseイベントを使用すると、データを表示するためのカスタム形式を作成できます。The Format and Parse events allow you to create custom formats for displaying data. たとえば、テーブル内のDecimalデータが型である場合、のValue ConvertEventArgsプロパティをFormatイベントの書式設定された値に設定することによって、データを現地の通貨形式で表示できます。For example, if the data in a table is of type Decimal, you can display the data in the local currency format by setting the Value property of the ConvertEventArgs to the formatted value in the Format event. その結果、 Parseイベントに表示される値を unformat する必要があります。You must consequently unformat the displayed value in the Parse event.

イベントParseは、次の状況で発生します。The Parse event occurs under the following conditions:

イベントの処理の詳細については、「処理とイベントの発生」を参照してください。For more information about handling events, see Handling and Raising Events.

適用対象

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