在本示例中,假設XtraGrid網格已被綁定到NWIND數據庫的[Order Details]表中。grid 網格中包含 "Quantity", "UnitPrice" 和 "Discount" 列,並且這幾列已被綁定到數據庫表的相應字段中。下面的例子主要演示如何爲gird網格添加一個非綁定列,從而顯示根據Quantity*UnitPrice*(1-Discount)公式計算出來的每個訂單的金額。
代碼如下:
C#
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(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(e.ListSourceRowIndex); }
VB
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 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(e.ListSourceRowIndex)
End Sub
結果顯示如下: