BindingSource.ResetBindings(Boolean) Method

Reference

Definition

Namespace:: System.Windows.Forms

Assembly:: System.Windows.Forms.dll

Important

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Causes a control bound to the BindingSource to reread all the items in the list and refresh their displayed values.

public:
 void ResetBindings(bool metadataChanged);

public void ResetBindings (bool metadataChanged);

member this.ResetBindings : bool -> unit

Public Sub ResetBindings (metadataChanged As Boolean)

Parameters

metadataChanged: Boolean

true if the data schema has changed; false if only values have changed.

Examples

The following code example uses a BindingSource component to bind an array list, which does not provide change notification. An item is removed from the list, and the bound controls are notified of the change by calling the ResetBindings method. This code example is part of a larger example provided in How to: Reflect Data Source Updates in a Windows Forms Control with the BindingSource.

private:
   void button1_Click( Object^ /*sender*/, EventArgs^ /*e*/ )
   {
      String^ xml = "<US><states>"
         + "<state><name>Washington</name><capital>Olympia</capital> "
         + "<flower>Coast Rhododendron</flower></state>"
         + "<state><name>Oregon</name><capital>Salem</capital>"
         + "<flower>Oregon Grape</flower></state>"
         + "<state><name>California</name><capital>Sacramento</capital>"
         + "<flower>California Poppy</flower></state>"
         + "<state><name>Nevada</name><capital>Carson City</capital>"
         + "<flower>Sagebrush</flower></state>"
         + "</states></US>";
      
      // Convert the xml string to bytes and load into a memory stream.
      array<Byte>^ xmlBytes = Encoding::UTF8->GetBytes( xml );
      MemoryStream^ stream = gcnew MemoryStream( xmlBytes,false );
      
      // Create a DataSet and load the xml into it.
      dataSet2->ReadXml( stream );
      
      // Set the data source.
      bindingSource1->DataSource = dataSet2;
      bindingSource1->ResetBindings( true );
   }

private void button1_Click(object sender, EventArgs e)
{
    // If items remain in the list, remove the first item. 
    if (states.Count > 0)
    {
        states.RemoveAt(0);

        // Call ResetBindings to update the textboxes.
        bindingSource1.ResetBindings(false);
    }
}


Private Sub button1_Click(ByVal sender As Object, ByVal e As EventArgs) _
    Handles button1.Click

    ' If items remain in the list, remove the first item. 
    If states.Count > 0 Then
        states.RemoveAt(0)

        ' Call ResetBindings to update the textboxes.
        bindingSource1.ResetBindings(False)
    End If

End Sub

Remarks

The ResetBindings method informs all controls bound to the BindingSource to refresh their values. The method does this by raising the ListChanged event at least once; the metaDataChanged parameter indicates the nature of the underlying change.

A metaDataChanged value of true indicates that the data schema of BindingSource has changed. A ListChanged event is raised with ListChangedEventArgs.ListChangedType set to ListChangedType.PropertyDescriptorChanged.
A metaDataChanged value of false indicates that only the values of one or more items have changed.

Regardless of the value of metaDataChanged, a ListChanged event is raised with ListChangedEventArgs.ListChangedType set to ListChangedType.Reset. As a consequence, calling ResetBindings with a parameter of true will raise two ListChanged events.

ResetBindings is automatically called whenever another member makes major changes to the data-binding, such as setting the DataSource or DataMember properties. However, the programmer can also call this method explicitly.

Applies to

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