Tip Using a SearchList as an alphabetic clickable index to columns in a huge DataGridView

[Rob Sherratt]

I Hope this code snippet might be useful to other people. I wanted to provide my users with a one-click alphabetical index mechanism to find column headings in a very large DataTable (> 5000 rows and over 200 columns of various headings displayed in a functional order but not alphabetic). I used a ListBox in my form which I renamed as "SearchList". I gave it vertical and horizontal scroll bars in Forms Designer and also set it to single cell selection mode. The user can click on any item in the alphabetical index, and the selection in the corresponding MyDataGridView is moved to that column heading, while the currently selected row is preserved. MyDataGridView is configured to only permit single cell selection. In the code snippet, MyDataTable is NOT the DataTable that is bound to MyDataGridView, but instead it just contains a single column headed "Name" and each row is one column name entry from MyDataGridView.

Private Sub Show_Search_List()

        ' Implements Column heading Search capability for MyDataGridView

        SearchList.Sorted = True
        SearchList.DataSource = New DataView(MyDataSet.Tables("MyDataTable containing list of column names in MyDataGridView"))
        SearchList.DisplayMember = "Name"   ' The first column in MyDataTable has the title "Name"
        SearchList.Show()

End Sub

Private Sub SearchList_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles SearchList.Click

        ' The SelectedItem in the SearchList browser will be a valid column name for MyDataGridView

        Dim MyColumnName As String = SearchList.Text
        Dim MySelRow As Integer = MyDataGridView.SelectedCells(0).RowIndex

        For Each cell As DataGridViewCell In MyDataGridView.SelectedCells
               cell.Selected = False
        Next cell

        ' This is the cell in MyDataGridView to select

        MyDataGridView.Rows(MySelRow).Cells(MyColumnName).Selected = True

End Sub

Regards,
Rob