VBA - How to create a cascading combo box in a userform-Computerfanfield

In this article you will learn how to fill a cascading combo box using the indirect method.

Prerequisites

1 Workbook

1 UserForm

3 Combobox

You can download a sample Workbook here.

Managing names under Excel

To define names in an Excel Workbook, you can either:

For Excel 2007 or earlier version: Insert > Names > Define .

Most current versions (from Excel 2010): Ribbon formulas > Define a name.

The code for the combobox

We want the following to happen:

Upon loading the UserForm, the Combox1 will be filled .

The other combo boxes will be filled based on the values of the first one.

Filling the first list

To fill a combo box with the contents of a named range of the workbook, the syntax is:

ComboBox1.List = Application.Transpose(Range("monNom"))

To clear the ComboBox:

Combobox1.Clear

What gives us the code for filling the first dropdown list at the loading of the UserForm:

Private Sub UserForm_Initialize() ComboBox1.Clear ComboBox1.List = Application.Transpose(Range("Dep")) ComboBox2.Clear ComboBox3.Clear End Sub

Filling the 2nd list

When a value is selected in the first drop-down list, it will (the text shown in the Combobox) correspond to a workbook name.

To display the contents of the cells of the named range, we will use the Change event:

Private Sub ComboBox1_Change() 'Combobox département Avoid the bug generated when a user deleted the content of ComboBox1 If ComboBox1.Value = "" Then Exit Sub ComboBox2.Clear ComboBox3.Clear ComboBox2.List = Application.Transpose(Range(NomRange)) End Sub

For the third combo box:

Private Sub ComboBox2_Change() 'Combobox communes If ComboBox2.Value = "" Then Exit Sub ComboBox3.Clear ComboBox3.List = Application.Transpose(Range(NomRange)) End Sub

Common bugs

Unnamed Range

The name entered in the Combobox won't match any workbook name. This happens when the name hasn't been defined. To circumvent this problem, we will create a small function to loop through all the names of the workbook:

Function NomDefini(Nom As String) As Boolean Dim Noms As Name NomDefini = False For Each Noms In ThisWorkbook.Names If Noms.Name = Nom Then NomDefini = True: Exit Function Next Noms End Function

Input error

As you will notice in the sample file, defining names do not take into account special characters or spaces. In some situations, you may need to edit the variables. Here's an example:

Function CaracSpec(Nom As String) As String CaracSpec = Replace(Nom, " ", "_") CaracSpec = Replace(CaracSpec, "-", "_") End Function

The completed code

Option Explicit Private Sub UserForm_Initialize() ComboBox1.Clear ComboBox1.List = Application.Transpose(Range("Dep")) ComboBox2.Clear ComboBox3.Clear End Sub Private Sub ComboBox1_Change() 'Combobox département If ComboBox1.Value = "" Then Exit Sub ComboBox2.Clear ComboBox3.Clear Dim NomRange As String NomRange = CaracSpec(ComboBox1.Value) If NomDefini(NomRange) Then ComboBox2.List = Application.Transpose(Range(NomRange)) Else ComboBox2.AddItem """Aucune commune""" End If End Sub Private Sub ComboBox2_Change() 'Combobox communes If ComboBox2.Value = "" Then Exit Sub ComboBox3.Clear Dim NomRange As String NomRange = CaracSpec(ComboBox2.Value) If NomDefini(NomRange) Then ComboBox3.List = Application.Transpose(Range(NomRange)) Else ComboBox3.AddItem """Aucune rue""" End If End Sub Function NomDefini(Nom As String) As Boolean Dim Noms As Name NomDefini = False For Each Noms In ThisWorkbook.Names If Noms.Name = Nom Then NomDefini = True: Exit Function Next Noms End Function Function CaracSpec(Nom As String) As String CaracSpec = Replace(Nom, " ", "_") CaracSpec = Replace(CaracSpec, "-", "_") End Function

Download link

Download the sample sheet here

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