How to: Add an Unbound Column Storing Arbitrary Data

  • 2 minutes to read

Assume that the Grid Control is bound to a table that contains the "Quantity", "UnitPrice" and "Discount" columns. The example below shows how to add an unbound column to the grid to display the amount of each order according to the expression: QuantityUnitPrice(1-Discount).

The result is displayed below:

CD_UnboundColumns_example

For another example which illustrates working with unbound columns, see the Unbound Columns tutorial.

using DevExpress.XtraGrid.Views.Base;
using DevExpress.XtraGrid.Views.Grid;
using DevExpress.XtraGrid.Columns;

private void Form1_Load(object sender, System.EventArgs e) {
   // ...
   gridControl1.ForceInitialize();

   // Create an unbound column.
   GridColumn unbColumn = gridView1.Columns.AddField("Total");
   unbColumn.VisibleIndex = gridView1.Columns.Count;
   unbColumn.UnboundType = DevExpress.Data.UnboundColumnType.Decimal;
   // Disable editing.
   unbColumn.OptionsColumn.AllowEdit = false;
   // Specify format settings.
   unbColumn.DisplayFormat.FormatType = DevExpress.Utils.FormatType.Numeric;
   unbColumn.DisplayFormat.FormatString = "c";
   // Customize the appearance settings.
   unbColumn.AppearanceCell.BackColor = Color.LemonChiffon;
}

// Returns the total amount for a specific row.
decimal getTotalValue(GridView view, int listSourceRowIndex) {
    decimal unitPrice = Convert.ToDecimal(view.GetListSourceRowCellValue(listSourceRowIndex, "UnitPrice"));
    decimal quantity = Convert.ToDecimal(view.GetListSourceRowCellValue(listSourceRowIndex, "Quantity"));
    decimal discount = Convert.ToDecimal(view.GetListSourceRowCellValue(listSourceRowIndex, "Discount"));
    return unitPrice * quantity * (1 - discount);
}

// Provides data for the Total column.
private void gridView1_CustomUnboundColumnData(object sender, CustomColumnDataEventArgs e) {
   GridView view = sender as GridView;
   if (e.Column.FieldName == "Total" && e.IsGetData) e.Value = 
     getTotalValue(view, e.ListSourceRowIndex);
}