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PictureBox.LoadCompleted Event

Definition

Occurs when the asynchronous image-load operation is completed, been canceled, or raised an exception.

public:
 event System::ComponentModel::AsyncCompletedEventHandler ^ LoadCompleted;
public event System.ComponentModel.AsyncCompletedEventHandler LoadCompleted;
public event System.ComponentModel.AsyncCompletedEventHandler? LoadCompleted;
member this.LoadCompleted : System.ComponentModel.AsyncCompletedEventHandler 
Public Custom Event LoadCompleted As AsyncCompletedEventHandler 

Event Type

Examples

The following code example demonstrates the use of this member. In the example, an event handler reports on the occurrence of the LoadCompleted 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 PictureBox named PictureBox1. Then ensure that the event handler is associated with the LoadCompleted event.

private void PictureBox1_LoadCompleted(Object sender, AsyncCompletedEventArgs e) {

System.Text.StringBuilder messageBoxCS = new System.Text.StringBuilder();
messageBoxCS.AppendFormat("{0} = {1}", "Cancelled", e.Cancelled );
messageBoxCS.AppendLine();
messageBoxCS.AppendFormat("{0} = {1}", "Error", e.Error );
messageBoxCS.AppendLine();
messageBoxCS.AppendFormat("{0} = {1}", "UserState", e.UserState );
messageBoxCS.AppendLine();
MessageBox.Show(messageBoxCS.ToString(), "LoadCompleted Event" );
}
Private Sub PictureBox1_LoadCompleted(sender as Object, e as AsyncCompletedEventArgs) _ 
     Handles PictureBox1.LoadCompleted

    Dim messageBoxVB as New System.Text.StringBuilder()
    messageBoxVB.AppendFormat("{0} = {1}", "Cancelled", e.Cancelled)
    messageBoxVB.AppendLine()
    messageBoxVB.AppendFormat("{0} = {1}", "Error", e.Error)
    messageBoxVB.AppendLine()
    messageBoxVB.AppendFormat("{0} = {1}", "UserState", e.UserState)
    messageBoxVB.AppendLine()
    MessageBox.Show(messageBoxVB.ToString(),"LoadCompleted Event")

End Sub

Remarks

The LoadCompleted occurs only when the image is loaded asynchronously by using one of the LoadAsync methods, and WaitOnLoad is false. If the image-load is canceled by calling the CancelAsync method the Cancelled property of the AsyncCompletedEventArgs will be set to true. If an exception or error occurs during the load process, it will be caught and the Error property of the AsyncCompletedEventArgs will contain the exception information.

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

Applies to