How can I make the context menu to close after a set time interval?

To automatically close the context menu after a set time interval, you can use a Timer and send a ESC key stroke after the desired time interval as shown:

[C#]
private void timer1_Tick(object sender, System.EventArgs e)
{
	SendKeys.Send('{ESC}');
	timer1.Stop();
}
private void contextMenu1_Popup(object sender, System.EventArgs e)
{
	//set interval to 5 seconds
	timer1.Interval = 5000;
	timer1.Start();
}

[VB.Net]

Private  Sub timer1_Tick(ByVal sender As Object, ByVal e As System.EventArgs)
	SendKeys.Send('{ESC}')
	timer1.Stop()
End Sub
Private  Sub contextMenu1_Popup(ByVal sender As Object, ByVal e As System.EventArgs)
	’set interval to 5 seconds
	timer1.Interval = 5000
	timer1.Start()
End Sub