假设 XtraGrid 被绑定到 NWind 数据库中的 [Order Details] 表。 网格控件包含了“Quantity”、“UnitPrice”和“Discount"”列，这些列被绑定到数据库表中的相应字段。 下面的示例展示了如何把一个非绑定列添加到网格控件中，根据表达式 Quantity*UnitPrice*(1-Discount) 来显示每张订单的合计。

如果显示如下：

另一个演示了使用非绑定列的示例，请参阅 非绑定列 指南。

C#CopyCode image复制代码
using DevExpress.XtraGrid.Views.Base;
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(ColumnView view, int listSourceRowIndex) {
    DataRow row = nwindDataSet.Tables["Order Details"].Rows[listSourceRowIndex];
    decimal unitPrice = Convert.ToDecimal(row["UnitPrice"]);
    decimal quantity = Convert.ToDecimal(row["Quantity"]);
    decimal discount = Convert.ToDecimal(row["Discount"]);
    return unitPrice * quantity * (1 - discount);
}

// Provides data for the Total column.
private void gridView1_CustomUnboundColumnData(object sender, CustomColumnDataEventArgs e) {
   if (e.Column.FieldName == "Total" && e.IsGetData) e.Value = 
     getTotalValue(sender as ColumnView, e.ListSourceRowIndex);
}
Visual BasicCopyCode image复制代码
Imports DevExpress.XtraGrid.Views.Base
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(ByVal view As ColumnView, _
  ByVal listSourceRowIndex As Integer) As Decimal
    Dim row As DataRow = NwindDataSet.Tables("Order Details").Rows(listSourceRowIndex)
    Dim unitPrice As Decimal = Convert.ToDecimal(row("UnitPrice"))
    Dim quantity As Decimal = Convert.ToDecimal(row("Quantity"))
    Dim discount As Decimal = Convert.ToDecimal(row("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
   If e.Column.FieldName = "Total" And e.IsGetData Then e.Value = _
     getTotalValue(CType(sender, ColumnView), e.ListSourceRowIndex)
End Sub