CollectionChangeEventArgs Class

Reference

Definition

Namespace:: System.ComponentModel

Assembly:: System.ComponentModel.TypeConverter.dll

Assembly:: System.dll

Assembly:: netstandard.dll

Source:: CollectionChangeEventArgs.cs

Source:: CollectionChangeEventArgs.cs

Source:: CollectionChangeEventArgs.cs

Important

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Provides data for the CollectionChanged event.

public ref class CollectionChangeEventArgs : EventArgs

public class CollectionChangeEventArgs : EventArgs

type CollectionChangeEventArgs = class
    inherit EventArgs

Public Class CollectionChangeEventArgs
Inherits EventArgs

Inheritance: Object

EventArgs
CollectionChangeEventArgs

Examples

The following code example demonstrates the use of this type. In the example, an event handler reports on the occurrence of the AutoCompleteStringCollection.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 AutoCompleteStringCollection named AutoCompleteStringCollection1. Then ensure that the event handler is associated with the AutoCompleteStringCollection.CollectionChanged event.

private void AutoCompleteStringCollection1_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 AutoCompleteStringCollection1_CollectionChanged(sender as Object, e as CollectionChangeEventArgs) _ 
     Handles AutoCompleteStringCollection1.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

A CollectionChanged event is raised when you change which items are in a collection, for example, by adding an element to a collection or removing an element from the collection. This event is not raised when an individual element changes its value.

Constructors

CollectionChangeEventArgs(CollectionChangeAction, Object)

Initializes a new instance of the CollectionChangeEventArgs class.

Properties

Action	Gets an action that specifies how the collection changed.
Element	Gets the instance of the collection with the change.

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

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