ToolStripItem.OnMouseEnter(EventArgs) Method

Definition

Namespace:

System.Windows.Forms

Assembly:

System.Windows.Forms.dll

Source:

ToolStripItem.cs

Raises the MouseEnter event.

protected:
 virtual void OnMouseEnter(EventArgs ^ e);

protected virtual void OnMouseEnter (EventArgs e);

abstract member OnMouseEnter : EventArgs -> unit
override this.OnMouseEnter : EventArgs -> unit

Protected Overridable Sub OnMouseEnter (e As EventArgs)

Parameters

e

EventArgs

An EventArgs that contains the event data.

Examples

The following code example demonstrates how to override the OnMouseEnter method. This code example is part of a larger example provided for the ToolStripItem class.

// This method defines the behavior of the MouseEnter event.
// It sets the state of the rolloverValue field to true and
// tells the control to repaint.
protected override void OnMouseEnter(EventArgs e)
{
    base.OnMouseEnter(e);

    this.rolloverValue = true;

    this.Invalidate();
}

' This method defines the behavior of the MouseEnter event.
' It sets the state of the rolloverValue field to true and
' tells the control to repaint.
Protected Overrides Sub OnMouseEnter(e As EventArgs)
   MyBase.OnMouseEnter(e)
   
   Me.rolloverValue = True
   
   Me.Invalidate()
 End Sub

Remarks

Raising an event invokes the event handler through a delegate. For more information, see Handling and Raising Events.

The OnMouseEnter method also allows derived classes to handle the event without attaching a delegate. This is the preferred technique for handling the event in a derived class.

Notes to Inheritors

When overriding OnMouseEnter(EventArgs) in a derived class, be sure to call the base class's OnMouseEnter(EventArgs) method so that registered delegates receive the event.