The following example uses the TripleState property to allow Null as a legal value of a CheckBox and a ToggleButton. The user controls the value of TripleState through ToggleButton2. The user can set the value of a CheckBox or ToggleButton based on the value of TripleState.

To use this example, copy this sample code to the Declarations portion of a form. Make sure that the form contains:

Private Sub UserForm_Initialize() CheckBox1.Caption = "Value is True" CheckBox1.Value = True CheckBox1.TripleState = False ToggleButton1.Caption = "Value is True" ToggleButton1.Value = True ToggleButton1.TripleState = False ToggleButton2.Value = False ToggleButton2.Caption = "Triple State Off" End Sub Private Sub ToggleButton2_Click() If ToggleButton2.Value = True Then ToggleButton2.Caption = "Triple State On" CheckBox1.TripleState = True ToggleButton1.TripleState = True Else ToggleButton2.Caption = "Triple State Off" CheckBox1.TripleState = False ToggleButton1.TripleState = False End If End Sub Private Sub CheckBox1_Change() If IsNull(CheckBox1.Value) Then CheckBox1.Caption = "Value is Null" ElseIf CheckBox1.Value = False Then CheckBox1.Caption = "Value is False" ElseIf CheckBox1.Value = True Then CheckBox1.Caption = "Value is True" End If End Sub Private Sub ToggleButton1_Change() If IsNull(ToggleButton1.Value) Then ToggleButton1.Caption = "Value is Null" ElseIf ToggleButton1.Value = False Then ToggleButton1.Caption = "Value is False" ElseIf ToggleButton1.Value = True Then ToggleButton1.Caption = "Value is True" End If End Sub