How to pull down the GridComboBoxColumn in Tab key in WinForms DataGrid?

In WinForms DataGrid (SfDataGrid), drop down of GridComboBoxColumn will open when double clicking the cell. But, you can open the drop down by press the Tab key using a custom renderer can be derived from GridComboBoxCellRenderer. In the custom renderer, the OnKeyUp method can be overridden to show the dropdown.

public class GridComboBoxCellRendererExt : GridComboBoxCellRenderer
{
    SfDataGrid dataGrid;
    SfComboBox SfCombo;
    public GridComboBoxCellRendererExt(SfDataGrid sfDataGrid)
    {
        dataGrid = sfDataGrid;
    }
    protected override void OnKeyUp(DataColumnBase dataColumn, RowColumnIndex rowColumnIndex, KeyEventArgs e)
    {
        if (e.KeyData == Keys.Tab)
        {
            dataGrid.CurrentCell.BeginEdit();
            //To open the dropdown
            SfCombo.ShowDropDown();
        }
    }
}

//To add custom ComboBox renderer to DataGrid
this.sfDataGrid.CellRenderers.Remove("ComboBox");
this.sfDataGrid.CellRenderers.Add("ComboBox", new GridComboBoxCellRendererExt(sfDataGrid));
//To add a combo box column in grid.
sfDataGrid.Columns.Add(new GridComboBoxColumn() { MappingName = "ShipCityID", HeaderText = "Ship City", ValueMember = "ShipCityID", DisplayMember = "ShipCityName", IDataSourceSelector = new CustomSelector() });

View sample in GitHub

Conclusion

I hope you enjoyed learning about how to pull down the GridComboBoxColumn in Tab key in DataGrid.

You can refer to our WinForms DataGrid feature tour page to know about its other groundbreaking feature representations and WinForms DataGrid documentation, and how to quickly get started for configuration specifications. You can also explore our  WinForms DataGrid example to understand how to create and manipulate data.

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