如何在DataGrid綁定之前為DataSet添加新列

來源:互聯網
上載者:User
datagrid

在實際的應用中經常會遇到根據其它列計算某一新列的結果,實現這樣的功能有兩種辦法:一個直接使用SQL語句;另外就是在綁定時進行動態添加。第一種方法以前已經介紹過。下面就是第二種方法的具體實現:

AddDataSetColumn.aspx

<%@ Page Language="vb" AutoEventWireup="false" Codebehind="AddDataSetColumn.<a href="http://www.chinaitpower.com/Dev/Web/Asp/index.html" target="_blank">asp</a>x.vb"

  Inherits="<a href="http://www.chinaitpower.com/Dev/Web/Asp/index.html" target="_blank">asp</a>xWeb.AddDataSetColumn"%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">

<HTML>

  <HEAD>

    <title>AddDataSetColumn</title>

    <meta name="GENERATOR" content="Microsoft Visual Studio .NET 7.1">

    <meta name="CODE_LANGUAGE" content="Visual Basic .NET 7.1">

    <meta name="vs_defaultClientScript" content="JavaScript">

    <meta name="vs_targetSchema" content="http://schemas.microsoft.com/intellisense/ie5">

  </HEAD>

  <body MS_POSITIONING="GridLayout">

    <form id="Form1" method="post" runat="server">

      <<a href="http://www.chinaitpower.com/Dev/Web/Asp/index.html" target="_blank">asp</a>:DataGrid id="DataGrid1" runat="server" AutoGenerateColumns="False"

        ShowFooter="True" Width="100%">

        <HeaderStyle Font-Names="宋體" Font-Bold="True" HorizontalAlign="Center"

         ForeColor="Navy" BackColor="LightSalmon"></HeaderStyle>

        <FooterStyle BackColor="#FFCCFF"></FooterStyle>

        <Columns>

          <<a href="http://www.chinaitpower.com/Dev/Web/Asp/index.html" target="_blank">asp</a>:TemplateColumn HeaderText="訂單號">

            <ItemTemplate>

              <<a href="http://www.chinaitpower.com/Dev/Web/Asp/index.html" target="_blank">asp</a>:Label ID="OrderID" Runat="server"></<a href="http://www.chinaitpower.com/Dev/Web/Asp/index.html" target="_blank">asp</a>:Label>

            </ItemTemplate>

          </<a href="http://www.chinaitpower.com/Dev/Web/Asp/index.html" target="_blank">asp</a>:TemplateColumn>

          <<a href="http://www.chinaitpower.com/Dev/Web/Asp/index.html" target="_blank">asp</a>:TemplateColumn HeaderText="產品號">

            <ItemTemplate>

              <<a href="http://www.chinaitpower.com/Dev/Web/Asp/index.html" target="_blank">asp</a>:Label ID="ProductID" Runat="server"></<a href="http://www.chinaitpower.com/Dev/Web/Asp/index.html" target="_blank">asp</a>:Label>

            </ItemTemplate>

          </<a href="http://www.chinaitpower.com/Dev/Web/Asp/index.html" target="_blank">asp</a>:TemplateColumn>

          <<a href="http://www.chinaitpower.com/Dev/Web/Asp/index.html" target="_blank">asp</a>:TemplateColumn HeaderText="單價">

            <ItemTemplate>

              <<a href="http://www.chinaitpower.com/Dev/Web/Asp/index.html" target="_blank">asp</a>:Label ID="UnitPrice" Runat="server"></<a href="http://www.chinaitpower.com/Dev/Web/Asp/index.html" target="_blank">asp</a>:Label>

            </ItemTemplate>

          </<a href="http://www.chinaitpower.com/Dev/Web/Asp/index.html" target="_blank">asp</a>:TemplateColumn>

          <<a href="http://www.chinaitpower.com/Dev/Web/Asp/index.html" target="_blank">asp</a>:TemplateColumn HeaderText="數量">

            <ItemTemplate>

              <<a href="http://www.chinaitpower.com/Dev/Web/Asp/index.html" target="_blank">asp</a>:Label ID="Quantity" Runat="server"></<a href="http://www.chinaitpower.com/Dev/Web/Asp/index.html" target="_blank">asp</a>:Label>

            </ItemTemplate>

          </<a href="http://www.chinaitpower.com/Dev/Web/Asp/index.html" target="_blank">asp</a>:TemplateColumn>

          <<a href="http://www.chinaitpower.com/Dev/Web/Asp/index.html" target="_blank">asp</a>:TemplateColumn HeaderText="折扣">

            <ItemTemplate>

              <<a href="http://www.chinaitpower.com/Dev/Web/Asp/index.html" target="_blank">asp</a>:Label ID="Discount" Runat="server"></<a href="http://www.chinaitpower.com/Dev/Web/Asp/index.html" target="_blank">asp</a>:Label>

            </ItemTemplate>

          </<a href="http://www.chinaitpower.com/Dev/Web/Asp/index.html" target="_blank">asp</a>:TemplateColumn>

          <<a href="http://www.chinaitpower.com/Dev/Web/Asp/index.html" target="_blank">asp</a>:TemplateColumn HeaderText="總計">

            <ItemTemplate>

              <<a href="http://www.chinaitpower.com/Dev/Web/Asp/index.html" target="_blank">asp</a>:Label ID="lblTotal" Runat="server"></<a href="http://www.chinaitpower.com/Dev/Web/Asp/index.html" target="_blank">asp</a>:Label>

            </ItemTemplate>

          </<a href="http://www.chinaitpower.com/Dev/Web/Asp/index.html" target="_blank">asp</a>:TemplateColumn>

        </Columns>

      </<a href="http://www.chinaitpower.com/Dev/Web/Asp/index.html" target="_blank">asp</a>:DataGrid>

    </form>

  </body>

</HTML>


AddDataSetColumn.aspx.vb

Imports System.Web.UI.WebControls

Public Class AddDataSetColumn

  Inherits System.Web.UI.Page

#Region " Web Form設計器產生的程式碼 "

  '該調用是 Web Form設計器所必需的。

  <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()

  End Sub

  Protected WithEvents DataGrid1 As System.Web.UI.WebControls.DataGrid

  '注意: 以下預留位置聲明是 Web Form設計器所必需的。

  '不要刪除或移動它。

  Private designerPlaceholderDeclaration As System.Object

  Private Sub Page_Init(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Init

    'CODEGEN: 此方法調用是 Web Form設計器所必需的

    '不要使用代碼編輯器修改它。

    InitializeComponent()

  End Sub

#End Region

  Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

    Dim strCnn As String = "Data Source=.\NetSDK; Initial Catalog=Northwind;User ID=sa;Password=;"

    Dim oCn As New System.Data.SqlClient.SqlConnection(strCnn)

    Dim strSql As System.String = "select * from [Order Details]"

    Dim ds As System.Data.DataSet = New System.Data.DataSet

    oCn.Open()

    Dim da As System.Data.SqlClient.SqlDataAdapter = New System.Data.SqlClient.SqlDataAdapter(strSql, oCn)

    ' 可以直接使用SQL語句實現,這個方法可以直接綁定,不需要用模板即可

    ' cmd.CommandText = "select *,UnitPrice * Quantity *(1- Discount) as Total from [Order Details]"

    ' 我們使用另外一種方法,在DataGrid綁定之前為DataSet添加一個列

    da.Fill(ds, "DS")

    Dim dvwGrid As DataView = ds.Tables(0).DefaultView

    DataGrid1.DataSource = dvwGrid

    DataGrid1.DataBind()

    oCn.Close()

    oCn.Dispose()

  End Sub

  Private Sub DataGrid1_ItemDataBound(ByVal sender As Object, ByVal e As DataGridItemEventArgs) _

    Handles DataGrid1.ItemDataBound

    Dim elemType As ListItemType = e.Item.ItemType

    If (elemType = ListItemType.Item Or elemType = ListItemType.AlternatingItem) Then

      '把DataItem轉換回DataRowView對象

      Dim myDataRowView As DataRowView = CType(e.Item.DataItem, DataRowView)

      Dim myDataRow As DataRow = myDataRowView.Row

      CType(e.Item.Cells(0).FindControl("OrderID"), Label).Text = myDataRow("OrderID")

      CType(e.Item.Cells(1).FindControl("ProductID"), Label).Text = myDataRow("ProductID")

      CType(e.Item.Cells(2).FindControl("UnitPrice"), Label).Text = myDataRow("UnitPrice")

      CType(e.Item.Cells(3).FindControl("Quantity"), Label).Text = myDataRow("Quantity")

      CType(e.Item.Cells(4).FindControl("Discount"), Label).Text = myDataRow("Discount")

      Dim dblPrice As Double = Double.Parse(myDataRow("UnitPrice"))

      Dim intQuantity As Integer = Int32.Parse(myDataRow("Quantity"))

      Dim intDiscount As Double = Double.Parse(myDataRow("Discount"))

      Dim nTotal As String = String.Format("{0:C}", dblPrice * (1 - intDiscount) * intQuantity)

      CType(e.Item.Cells(5).FindControl("lblTotal"), Label).Text = nTotal

    End If

  End Sub

End Class



相關文章

E-Commerce Solutions

Leverage the same tools powering the Alibaba Ecosystem

Learn more >

Apsara Conference 2019

The Rise of Data Intelligence, September 25th - 27th, Hangzhou, China

Learn more >

Alibaba Cloud Free Trial

Learn and experience the power of Alibaba Cloud with a free trial worth $300-1200 USD

Learn more >

聯繫我們

該頁面正文內容均來源於網絡整理,並不代表阿里雲官方的觀點,該頁面所提到的產品和服務也與阿里云無關,如果該頁面內容對您造成了困擾,歡迎寫郵件給我們,收到郵件我們將在5個工作日內處理。

如果您發現本社區中有涉嫌抄襲的內容,歡迎發送郵件至: info-contact@alibabacloud.com 進行舉報並提供相關證據,工作人員會在 5 個工作天內聯絡您,一經查實,本站將立刻刪除涉嫌侵權內容。