A ComboBox in a DataGrid

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Introduction

This is a descendant from DataGridColumnStyle and is used to have a ComboBox in a DataGrid column. It is based on an article by Sudhakar Jalli but I found the code not working. I repaired the code and cleaned it up a little.

The DataGridComboBoxColumn class makes it possible to have a ComboBox instead of the default text or checkbox. It took me quite a while to figure it out (even with the help of the article by Sudhakar Jalli). Using it is straightforward.

Using the code

First create a new DataGridTableStyle and make sure the mapping is set to the name of the table in the DataSource where the columns will belong to.

DataGridTableStyle ts=new DataGridTableStyle();
ts.MappingName="Columns";

Then, create the DataTable with the lookup values. This could of course come from the database (And it should BTW)

DataTable AccessDataTypes = new DataTable();
AccessDataTypes.Columns.Add(new DataColumn("Number", typeof(int)));
AccessDataTypes.Columns.Add(new DataColumn("Name", typeof(string)));
AccessDataTypes.Rows.Add(new object[] {3, "Numeric"});
AccessDataTypes.Rows.Add(new object[] {130, "Text"});

Create the DataGridComboBoxColumn and add it to the GridColumnStyles. The first argument (Type) is used for the column caption and the mapping. (Could be changed after creating). The second argument (AccessDataTypes) is the DataTable to use for translation. Name and Number are the column names to use from the table and theGrid is the DataGrid where this column will belong to. Be sure to provide the NullText ; if you don't it will throw an exception if you try to add a row to the DataGrid.

DataGridComboBoxColumn c1=new DataGridComboBoxColumn("Type", 
         AccessDataTypes, "Name", "Number", theGrid);
c1.NullText="3";
ts.GridColumnStyles.Add(c1);

Finally add the newly created TableStyle to the TableStyles array of the DataGrid.

theGrid.TableStyles.Add(ts);

Enjoy the improved DataGrid and be sure to send in your own DataGrid columns!