How to: Add an Unbound Column Storing Arbitrary Data
- 2 minutes to read
In the following example, it is assumed that the Grid Control is bound to a table that contains the “Quantity”, “UnitPrice”, and “Discount” columns. The code below adds an unbound column that calculates the total order amount according to the following expression: Quantity * UnitPrice * (1-Discount).
using DevExpress.XtraGrid.Views.Base;
using DevExpress.XtraGrid.Views.Grid;
using DevExpress.XtraGrid.Columns;
private void Form1_Load(object sender, EventArgs e) {
// ...
gridControl1.ForceInitialize();
// Create an unbound column.
GridColumn unboundColumn = gridView1.Columns.AddField("Total");
unboundColumn.VisibleIndex = gridView1.Columns.Count;
unboundColumn.UnboundDataType = typeof(decimal);
// Disable column edit operations.
unboundColumn.OptionsColumn.AllowEdit = false;
// Specify format settings.
unboundColumn.DisplayFormat.FormatType = DevExpress.Utils.FormatType.Numeric;
unboundColumn.DisplayFormat.FormatString = "c";
// Customize appearance settings.
unboundColumn.AppearanceCell.BackColor = Color.FromArgb(179, 226, 221);
}
// Return 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);
}
// Specify 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);
}