Uredi

Deli z drugimi prek

ScrollableControl.Scroll Event

  • Reference

Definition

Namespace:
System.Windows.Forms
Assembly:
System.Windows.Forms.dll

Occurs when the user or code scrolls through the client area.

public:
 event System::Windows::Forms::ScrollEventHandler ^ Scroll;
public event System.Windows.Forms.ScrollEventHandler Scroll;
public event System.Windows.Forms.ScrollEventHandler? Scroll;
member this.Scroll : System.Windows.Forms.ScrollEventHandler 
Public Custom Event Scroll As ScrollEventHandler

Event Type

ScrollEventHandler

Examples

The following code example demonstrates the use of this member. In the example, an event handler reports on the occurrence of the Scroll 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 a type that inherits from ScrollableControl, such as a Panel or ContainerControl. Then name the instance ScrollableControl1 and ensure that the event handler is associated with the Scroll event.

private void ScrollableControl1_Scroll(Object sender, ScrollEventArgs e) {

System.Text.StringBuilder messageBoxCS = new System.Text.StringBuilder();
messageBoxCS.AppendFormat("{0} = {1}", "ScrollOrientation", e.ScrollOrientation );
messageBoxCS.AppendLine();
messageBoxCS.AppendFormat("{0} = {1}", "Type", e.Type );
messageBoxCS.AppendLine();
messageBoxCS.AppendFormat("{0} = {1}", "NewValue", e.NewValue );
messageBoxCS.AppendLine();
messageBoxCS.AppendFormat("{0} = {1}", "OldValue", e.OldValue );
messageBoxCS.AppendLine();
MessageBox.Show(messageBoxCS.ToString(), "Scroll Event" );
}

Private Sub ScrollableControl1_Scroll(sender as Object, e as ScrollEventArgs) _ 
     Handles ScrollableControl1.Scroll

    Dim messageBoxVB as New System.Text.StringBuilder()
    messageBoxVB.AppendFormat("{0} = {1}", "ScrollOrientation", e.ScrollOrientation)
    messageBoxVB.AppendLine()
    messageBoxVB.AppendFormat("{0} = {1}", "Type", e.Type)
    messageBoxVB.AppendLine()
    messageBoxVB.AppendFormat("{0} = {1}", "NewValue", e.NewValue)
    messageBoxVB.AppendLine()
    messageBoxVB.AppendFormat("{0} = {1}", "OldValue", e.OldValue)
    messageBoxVB.AppendLine()
    MessageBox.Show(messageBoxVB.ToString(),"Scroll Event")

End Sub

Remarks

The Scroll event occurs when the user scrolls through the client area by interacting with the scroll bars, or when the user navigates between controls and the active control scrolls into view. The Scroll event also occurs when you write code, such as setting the AutoScrollPosition property, that scrolls through the client area.

You can use the ScrollOrientation property in your event handler to determine the scroll bar orientation for the Scroll event.

For more information about how to handle events, see Handling and Raising Events.

Applies to

See also