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Binding.Parse Event

Occurs when the value of a data-bound control changes.

Namespace: System.Windows.Forms
Assembly: System.Windows.Forms (in system.windows.forms.dll)

public:
event ConvertEventHandler^ Parse {
	void add (ConvertEventHandler^ value);
	void remove (ConvertEventHandler^ value);
}
/** @event */
public void add_Parse (ConvertEventHandler value)

/** @event */
public void remove_Parse (ConvertEventHandler value)

JScript supports the use of events, but not the declaration of new ones.

The Format and Parse events allow you to create custom formats for displaying data. 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. You must consequently unformat the displayed value in the Parse event.

The Parse event occurs under the following conditions:

For more information about handling events, see Consuming Events.

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. The DecimalToCurrencyString event delegate, added to the Format event, formats the bound value (a Decimal type) as currency using the ToString method. The 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.get_DesiredType().Equals(String.class.ToType())) {
        return;
    }
    // Use the ToString method to format the value as currency ("c").
    cevent.set_Value(((System.Decimal)(cevent.get_Value())).ToString("c"));
} //DecimalToCurrencyString

private void CurrencyStringToDecimal(Object sender, ConvertEventArgs cevent)
{
    // The method converts back to decimal type only.
    if (!cevent.get_DesiredType().Equals(System.Decimal.class.ToType())) {
        return;
    }
    // Converts the string back to decimal using the static Parse method.
    cevent.set_Value(Decimal.Parse(cevent.get_Value().ToString(), 
        NumberStyles.Currency, null));
} //CurrencyStringToDecimal

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.add_Format(new ConvertEventHandler(DecimalToCurrencyString));
    b.add_Parse(new ConvertEventHandler(CurrencyStringToDecimal));
    text1.get_DataBindings().Add(b);
} //BindControl

private function DecimalToCurrencyString(sender, cevent : ConvertEventArgs)
{
   // The method converts only to string type. Test this using the DesiredType.
   if(cevent.DesiredType != String.GetType()) return;

   cevent.Value = (Decimal(cevent.Value)).ToString("c"); 
}

private function CurrencyStringToDecimal(sender, cevent : ConvertEventArgs)
{
   // The method converts back to decimal type only. 
   if(cevent.DesiredType != Decimal.GetType()) return;

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

private function BindControl()
{
   // Creates the binding first. The OrderAmount is a Decimal type.
   var b : Binding = new Binding
      ("Text", ds, "Suppliers.CompanyName");
   // Add the delegates to the event.
   b.add_Format(DecimalToCurrencyString);
   b.add_Parse(CurrencyStringToDecimal);
   text1.DataBindings.Add(b);
}


Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

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

.NET Framework

Supported in: 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 2.0, 1.0

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