Visual Basic code snippet - How to populate data in a ComboBox using DataTable

Populate ComboBox using DataTable

This .Net (VB) Visual Basic code snippet populate UI ComboBox with given DataTable. Simply pass ComboBox UI object , DataTable with values, DataTable Value field name and DataTable display field name. Using given DataTable fields this function will populate ComboBox dropdown menu. Optionally you can pass default display value to be displayed when ComboBox data populated. DataTable can be generated using a Database or by manually creating static data.

''' <summary>
''' Creates the drop down menu.
''' </summary>
''' <param name="_tmpComboBox">The combo box.</param>
''' <param name="_DataSource">The datasource.</param>
''' <param name="_ValueMember">The value member.</param>
''' <param name="_DisplayMember">The display member.</param>
''' <param name="_DefaultDisp">The default display value (Optional).</param>
Public Sub CreateDropDownMenu(ByRef _tmpComboBox As ComboBox, ByVal _DataSource As DataTable, ByVal _ValueMember As String, ByVal _DisplayMember As String, ByVal _DefaultDisp As String)
    If _DataSource IsNot Nothing Then
        ' Set display, value options
        _tmpComboBox.ValueMember = _ValueMember
        _tmpComboBox.DisplayMember = _DisplayMember

        ' Create custom row
        If _DefaultDisp IsNot Nothing Then
            Dim _row As DataRow = _DataSource.NewRow()
            _row(1) = _DefaultDisp
            _row(0) = 0

            ' Insert Custom row at beginning
            _DataSource.Rows.InsertAt(_row, 0)
        End If

        _tmpComboBox.DataSource = _DataSource
        _tmpComboBox.SelectedIndex = 0
    End If
End Sub
Public Sub CreateDropDownMenu(ByRef _tmpComboBox As ComboBox, ByVal _DataSource As DataTable, ByVal _ValueMember As String, ByVal _DisplayMember As String)
    CreateDropDownMenu(_tmpComboBox, _DataSource, _ValueMember, _DisplayMember, Nothing)
End Sub

Here is a simple example showing how to use above function (CreateDropDownMenu) to populate ComboBox drop down menu with values.

 
Dim _DataTable AS DataTable  = ... Apply your methods to populate DataTable ...

CreateDropDownMenu(ref comboBox1, _DataTable, "VALUE_FIELD_NAME", "DISPLAY_FIELD_NAME", " - Select - ")

- or -

CreateDropDownMenu(ref comboBox1, _DataTable, "VALUE_FIELD_NAME", "DISPLAY_FIELD_NAME")

VB Keywords Used:

• DataTable
• ComboBox
• DataRow
• ValueMember
• DisplayMember

Code Snippet Information:

• Applies To: .Net, VB, Visual Basic, CLI, SQL, DataTable, SQL Server, SQL Client, ComboBox, Drop down menu
• Programming Language : Visual Basic (VB)

External Resources:

• DataTable Class
• ComboBox

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