BindingsCollection.CollectionChanged Event

Definition

Namespace:

System.Windows.Forms

Assembly:

System.Windows.Forms.dll

Occurs when the collection has changed.

public:
 event System::ComponentModel::CollectionChangeEventHandler ^ CollectionChanged;

public event System.ComponentModel.CollectionChangeEventHandler? CollectionChanged;

member this.CollectionChanged : System.ComponentModel.CollectionChangeEventHandler 

Public Custom Event CollectionChanged As CollectionChangeEventHandler 

Event Type

CollectionChangeEventHandler

Examples

The following code example demonstrates the use of this member. In the example, an event handler reports on the occurrence of the CollectionChanged event. This report helps you to learn when the event occurs and can assist you in debugging. To report on multiple events or on events that occur frequently, consider replacing MessageBox.Show with Console.WriteLine or appending the message to a multiline TextBox.

To run the example code, paste it into a project that contains an instance of type BindingsCollection named BindingsCollection1. Then ensure that the event handler is associated with the CollectionChanged event.

private void BindingsCollection1_CollectionChanged(Object sender, CollectionChangeEventArgs e) {

System.Text.StringBuilder messageBoxCS = new System.Text.StringBuilder();
messageBoxCS.AppendFormat("{0} = {1}", "Action", e.Action );
messageBoxCS.AppendLine();
messageBoxCS.AppendFormat("{0} = {1}", "Element", e.Element );
messageBoxCS.AppendLine();
MessageBox.Show(messageBoxCS.ToString(), "CollectionChanged Event" );
}

Private Sub BindingsCollection1_CollectionChanged(sender as Object, e as CollectionChangeEventArgs) _ 
     Handles BindingsCollection1.CollectionChanged

    Dim messageBoxVB as New System.Text.StringBuilder()
    messageBoxVB.AppendFormat("{0} = {1}", "Action", e.Action)
    messageBoxVB.AppendLine()
    messageBoxVB.AppendFormat("{0} = {1}", "Element", e.Element)
    messageBoxVB.AppendLine()
    MessageBox.Show(messageBoxVB.ToString(),"CollectionChanged Event")

End Sub

Remarks

For more information about handling events, see Handling and Raising Events.