Raising an event invokes the event handler through a delegate.
The OnValueChanged 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 OnValueChanged in a derived class, be sure to call the base class's OnValueChanged method so that registered delegates receive the event.
Private Sub ultraCalendarCombo1_ValueChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles ultraCalendarCombo1.ValueChanged Dim valueString As String = "Nothing" If (Not Me.ultraCalendarCombo1.Value Is Nothing) Then valueString = Me.ultraCalendarCombo1.Value End If Debug.WriteLine("The new value is: '" + valueString + "'") End Sub
private void ultraCalendarCombo1_ValueChanged(object sender, System.EventArgs e) { string valueString = "null"; if ( this.ultraCalendarCombo1.Value != null ) valueString = this.ultraCalendarCombo1.Value.ToString(); System.Diagnostics.Debug.WriteLine("The new value is: '" + valueString + "'"); }
Target Platforms: Windows 10, Windows 8.1, Windows 8, Windows 7, Windows Server 2012, Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2