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ListChangedEventArgs Class

Definition

Provides data for the ListChanged event.

public ref class ListChangedEventArgs : EventArgs
public class ListChangedEventArgs : EventArgs
type ListChangedEventArgs = class
    inherit EventArgs
Public Class ListChangedEventArgs
Inherits EventArgs
Inheritance
ListChangedEventArgs

Examples

The following code example demonstrates the use of this type. In the example, an event handler reports on the occurrence of the BindingSource.ListChanged 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 BindingSource named BindingSource1. Then ensure that the event handler is associated with the BindingSource.ListChanged event.

private void BindingSource1_ListChanged(Object sender, ListChangedEventArgs e) {

System.Text.StringBuilder messageBoxCS = new System.Text.StringBuilder();
messageBoxCS.AppendFormat("{0} = {1}", "ListChangedType", e.ListChangedType );
messageBoxCS.AppendLine();
messageBoxCS.AppendFormat("{0} = {1}", "NewIndex", e.NewIndex );
messageBoxCS.AppendLine();
messageBoxCS.AppendFormat("{0} = {1}", "OldIndex", e.OldIndex );
messageBoxCS.AppendLine();
messageBoxCS.AppendFormat("{0} = {1}", "PropertyDescriptor", e.PropertyDescriptor );
messageBoxCS.AppendLine();
MessageBox.Show(messageBoxCS.ToString(), "ListChanged Event" );
}
Private Sub BindingSource1_ListChanged(sender as Object, e as ListChangedEventArgs) _ 
     Handles BindingSource1.ListChanged

    Dim messageBoxVB as New System.Text.StringBuilder()
    messageBoxVB.AppendFormat("{0} = {1}", "ListChangedType", e.ListChangedType)
    messageBoxVB.AppendLine()
    messageBoxVB.AppendFormat("{0} = {1}", "NewIndex", e.NewIndex)
    messageBoxVB.AppendLine()
    messageBoxVB.AppendFormat("{0} = {1}", "OldIndex", e.OldIndex)
    messageBoxVB.AppendLine()
    messageBoxVB.AppendFormat("{0} = {1}", "PropertyDescriptor", e.PropertyDescriptor)
    messageBoxVB.AppendLine()
    MessageBox.Show(messageBoxVB.ToString(),"ListChanged Event")

End Sub

Remarks

A ListChanged event is raised when the data in an IBindingList changes.

The NewIndex property indicates the index of the item that was added, changed, or deleted. If an item was moved, the NewIndex property indicates the new location of the item and the OldIndex property indicates the old location.

If only one item is affected by a change, the OldIndex property value is -1.

Constructors

ListChangedEventArgs(ListChangedType, Int32, Int32)

Initializes a new instance of the ListChangedEventArgs class given the type of change and the old and new index of the item that was moved.

ListChangedEventArgs(ListChangedType, Int32, PropertyDescriptor)

Initializes a new instance of the ListChangedEventArgs class given the type of change, the index of the affected item, and a PropertyDescriptor describing the affected item.

ListChangedEventArgs(ListChangedType, Int32)

Initializes a new instance of the ListChangedEventArgs class given the type of change and the index of the affected item.

ListChangedEventArgs(ListChangedType, PropertyDescriptor)

Initializes a new instance of the ListChangedEventArgs class given the type of change and the PropertyDescriptor affected.

Properties

ListChangedType

Gets the type of change.

NewIndex

Gets the index of the item affected by the change.

OldIndex

Gets the old index of an item that has been moved.

PropertyDescriptor

Gets the PropertyDescriptor that was added, changed, or deleted.

Methods

Equals(Object)

Determines whether the specified object is equal to the current object.

(Inherited from Object)
GetHashCode()

Serves as the default hash function.

(Inherited from Object)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
ToString()

Returns a string that represents the current object.

(Inherited from Object)

Applies to

See also