How to: Add an Unbound Column Storing Arbitrary Data

• Nov 13, 2018
• 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:

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

C#

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);
}

VB.NET

Imports DevExpress.XtraGrid.Views.Base
Imports DevExpress.XtraGrid.Views.Grid
Imports DevExpress.XtraGrid.Columns

Private Sub Form1_Load(ByVal sender As System.Object, _
  ByVal e As System.EventArgs) Handles MyBase.Load
   ' ...
   gridControl1.ForceInitialize()

   ' Create an unbound column.
   Dim unbColumn As GridColumn = 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
End Sub

' Returns the total amount for a specific row.
Private Function getTotalValue(view As GridView, listSourceRowIndex As Integer) As Decimal
    Dim unitPrice As Decimal = Convert.ToDecimal(view.GetListSourceRowCellValue(listSourceRowIndex, "UnitPrice"))
    Dim quantity As Decimal = Convert.ToDecimal(view.GetListSourceRowCellValue(listSourceRowIndex, "Quantity"))
    Dim discount As Decimal = Convert.ToDecimal(view.GetListSourceRowCellValue(listSourceRowIndex, "Discount"))
    Return unitPrice * quantity * (1 - discount)
End Function

' Provides data for the Total column.
Private Sub GridView1_CustomUnboundColumnData(ByVal sender As Object, _
  ByVal e As CustomColumnDataEventArgs) Handles GridView1.CustomUnboundColumnData
   Dim view As GridView = TryCast(sender, GridView)
   If e.Column.FieldName = "Total" AndAlso e.IsGetData Then
      e.Value = getTotalValue(view, e.ListSourceRowIndex)
   End If
End Sub