DataGridColumnCollection.AddAt(Int32, DataGridColumn) Yöntem

Tanım

Belirtilen dizinde koleksiyona DataGridColumnCollection türetilmiş bir DataGridColumnsütun nesnesi ekler.

public:
 void AddAt(int index, System::Web::UI::WebControls::DataGridColumn ^ column);
public void AddAt (int index, System.Web.UI.WebControls.DataGridColumn column);
member this.AddAt : int * System.Web.UI.WebControls.DataGridColumn -> unit
Public Sub AddAt (index As Integer, column As DataGridColumn)

Parametreler

index
Int32

Türetilmiş sütunun DataGridColumneklendiği dizin konumuDataGridColumnCollection.

column
DataGridColumn

DataGridColumniçine eklenecek DataGridColumnCollection-derived sütunu.

Özel durumlar

column, null değeridir.

Örnekler

Aşağıdaki kod örneği, denetime dinamik olarak sütun eklemek için yönteminin DataGrid nasıl kullanılacağını AddAt gösterir. Denetimin Columns özelliğinin DataGrid koleksiyonun DataGridColumnCollection bir örneği olduğunu unutmayın.

<%@ Page Language="C#" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
 
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
   <script language="C#" runat="server">
 
      DataTable Cart;
      DataView CartView;
 
      ICollection CreateDataSource() 
      {
         DataTable dt = new DataTable();
         DataRow dr;
 
         dt.Columns.Add(new DataColumn("IntegerValue", typeof(Int32)));
         dt.Columns.Add(new DataColumn("StringValue", typeof(string)));
         dt.Columns.Add(new DataColumn("CurrencyValue", typeof(double)));
 
         for (int i = 0; i < 9; i++) 
         {
            dr = dt.NewRow();
   
            dr[0] = i;
            dr[1] = "Item " + i.ToString();
            dr[2] = 1.23 * (i + 1);
 
            dt.Rows.Add(dr);
         }
 
         DataView dv = new DataView(dt);
         return dv;
      } 
 
      void Page_Load(Object sender, EventArgs e) 
      {

         if (Session["DG4_ShoppingCart"] == null) 
         {
            Cart = new DataTable();
            Cart.Columns.Add(new DataColumn("Item", typeof(string)));
            Cart.Columns.Add(new DataColumn("Price", typeof(string)));
            Session["DG4_ShoppingCart"] = Cart;
         }
         else 
         {
            Cart = (DataTable)Session["DG4_ShoppingCart"];
         }    
         CartView = new DataView(Cart);
         ShoppingCart.DataSource = CartView;
         ShoppingCart.DataBind();
 
         if (!IsPostBack) 
         {
            // Load this data only once.
            ItemsGrid.DataSource= CreateDataSource();
            ItemsGrid.DataBind();
         }

      }

      void Page_Init(Object sender, EventArgs e) 
      {

         // Create a dynamic column to add to Columns collection.
         BoundColumn NumberColumn = new BoundColumn();
         NumberColumn.HeaderText="Item Number"; 
         NumberColumn.DataField="IntegerValue";

         // Add column to Columns collection.
         ItemsGrid.Columns.AddAt(2, NumberColumn);

      }
  
      void Grid_CartCommand(Object sender, DataGridCommandEventArgs e) {
     
         DataRow dr = Cart.NewRow();
          
         // e.Item is the table row where the command is raised.
         // For bound columns, the value is stored in the Text property of the TableCell.
         TableCell itemCell = e.Item.Cells[2];
         TableCell priceCell = e.Item.Cells[3];
         string item = itemCell.Text;
         string price = priceCell.Text;
         
         if (((Button)e.CommandSource).CommandName == "AddToCart") 
         {
            dr[0] = item;
            dr[1] = price;
            Cart.Rows.Add(dr);
         }
         else 
         { 

            //Remove from Cart.
         
            CartView.RowFilter = "Item='" + item + "'";
            if (CartView.Count > 0) 
            {    
               CartView.Delete(0);
            }
            CartView.RowFilter = "";
         }
         ShoppingCart.DataBind();
 
      }
 
   </script>
 
<head runat="server">
    <title>DataGridColumnCollection AddAt Example</title>
</head>
<body>
 
   <form id="form1" runat="server">
 
      <h3>DataGridColumnCollection AddAt Example</h3>
 
      <table cellpadding="5">
         <tr valign="top">
            <td>
 
               <b>Product List</b>
 
               <asp:DataGrid id="ItemsGrid"
                    BorderColor="black"
                    BorderWidth="1"
                    CellPadding="3"
                    AutoGenerateColumns="false"
                    OnItemCommand="Grid_CartCommand"
                    runat="server">

                  <HeaderStyle BackColor="#00aaaa">
                  </HeaderStyle>
 
                  <Columns>
 
                     <asp:ButtonColumn 
                          HeaderText="Add to cart" 
                          ButtonType="PushButton" 
                          Text="Add" 
                          CommandName="AddToCart"/>
 
                     <asp:ButtonColumn 
                          HeaderText="Remove from cart" 
                          ButtonType="PushButton" 
                          Text="Remove" 
                          CommandName="RemoveFromCart"/>
 
                     <asp:BoundColumn 
                          HeaderText="Item" 
                          DataField="StringValue"/>
 
                     <asp:BoundColumn 
                          HeaderText="Price" 
                          DataField="CurrencyValue" 
                          DataFormatString="{0:c}">

                        <ItemStyle HorizontalAlign="right">
                        </ItemStyle>

                     </asp:BoundColumn>
 
                  </Columns>
   
               </asp:DataGrid>
 
            </td>
            <td>
 
               <b>Shopping Cart</b>
 
               <asp:DataGrid id="ShoppingCart" 
                    runat="server"
                    BorderColor="black"
                    BorderWidth="1"
                    GridLines="Both"
                    ShowFooter="false"
                    CellPadding="3"
                    CellSpacing="0">

                  <HeaderStyle BackColor="#00aaaa">
                  </HeaderStyle>

                </asp:DataGrid>
 
            </td>
         </tr>
 
      </table>
 
   </form>
 
</body>
</html>
<%@ Page Language="VB" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
 
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
   <script language="VB" runat="server">
 
        Dim Cart As DataTable
        Dim CartView As DataView
 
        Function CreateDataSource() As ICollection
            Dim dt As New DataTable()
            Dim dr As DataRow
            
            dt.Columns.Add(New DataColumn("IntegerValue", GetType(Int32)))
            dt.Columns.Add(New DataColumn("StringValue", GetType(String)))
            dt.Columns.Add(New DataColumn("CurrencyValue", GetType(Double)))
            
            Dim i As Integer
            For i = 0 To 8
                dr = dt.NewRow()
                
                dr(0) = i
                dr(1) = "Item " & i.ToString()
                dr(2) = 1.23 *(i + 1)
                
                dt.Rows.Add(dr)
            Next i
            
            Dim dv As New DataView(dt)
            Return dv
        End Function 'CreateDataSource


        Sub Page_Load(sender As Object, e As EventArgs)
            
            If Session("DG4_ShoppingCart") Is Nothing Then
                Cart = New DataTable()
                Cart.Columns.Add(New DataColumn("Item", GetType(String)))
                Cart.Columns.Add(New DataColumn("Price", GetType(String)))
                Session("DG4_ShoppingCart") = Cart
            Else
                Cart = CType(Session("DG4_ShoppingCart"), DataTable)
            End If
            CartView = New DataView(Cart)
            ShoppingCart.DataSource = CartView
            ShoppingCart.DataBind()
            
            If Not IsPostBack Then
                ' Load this data only once.
                ItemsGrid.DataSource = CreateDataSource()
                ItemsGrid.DataBind()
            End If
        End Sub 'Page_Load
         

        Sub Page_Init(sender As Object, e As EventArgs)
            
            ' Create a dynamic column to add to Columns collection.
            Dim NumberColumn As New BoundColumn()
            NumberColumn.HeaderText = "Item Number"
            NumberColumn.DataField = "IntegerValue"
            
            ' Add column to Columns collection.
            ItemsGrid.Columns.AddAt(2, NumberColumn)
        End Sub 'Page_Init
         

        Sub Grid_CartCommand(sender As Object, e As DataGridCommandEventArgs)
            
            Dim dr As DataRow = Cart.NewRow()
            
            ' e.Item is the table row where the command is raised.
            ' For bound columns, the value is stored in the Text property of the TableCell.
            Dim itemCell As TableCell = e.Item.Cells(2)
            Dim priceCell As TableCell = e.Item.Cells(3)
            Dim item As String = itemCell.Text
            Dim price As String = priceCell.Text
            
            If CType(e.CommandSource, Button).CommandName = "AddToCart" Then
                dr(0) = item
                dr(1) = price
                Cart.Rows.Add(dr)
            Else 'Remove from Cart.
                CartView.RowFilter = "Item='" & item & "'"
                If CartView.Count > 0 Then
                    CartView.Delete(0)
                End If
                CartView.RowFilter = ""
            End If
            ShoppingCart.DataBind()
        End Sub 'Grid_CartCommand  
 
   </script>
 
<head runat="server">
    <title>DataGridColumnCollection AddAt Example</title>
</head>
<body>
 
   <form id="form1" runat="server">
 
      <h3>DataGridColumnCollection AddAt Example</h3>
 
      <table cellpadding="5">
         <tr valign="top">
            <td>
 
               <b>Product List</b>
 
               <asp:DataGrid id="ItemsGrid"
                    BorderColor="black"
                    BorderWidth="1"
                    CellPadding="3"
                    AutoGenerateColumns="false"
                    OnItemCommand="Grid_CartCommand"
                    runat="server">

                  <HeaderStyle BackColor="#00aaaa">
                  </HeaderStyle>
 
                  <Columns>
 
                     <asp:ButtonColumn 
                          HeaderText="Add to cart" 
                          ButtonType="PushButton" 
                          Text="Add" 
                          CommandName="AddToCart"/>
 
                     <asp:ButtonColumn 
                          HeaderText="Remove from cart" 
                          ButtonType="PushButton" 
                          Text="Remove" 
                          CommandName="RemoveFromCart"/>
 
                     <asp:BoundColumn 
                          HeaderText="Item" 
                          DataField="StringValue"/>
 
                     <asp:BoundColumn 
                          HeaderText="Price" 
                          DataField="CurrencyValue" 
                          DataFormatString="{0:c}">

                        <ItemStyle HorizontalAlign="right">
                        </ItemStyle>

                     </asp:BoundColumn>
 
                  </Columns>
   
               </asp:DataGrid>
 
            </td>
            <td>
 
               <b>Shopping Cart</b>
 
               <asp:DataGrid id="ShoppingCart" 
                    runat="server"
                    BorderColor="black"
                    BorderWidth="1"
                    GridLines="Both"
                    ShowFooter="false"
                    CellPadding="3"
                    CellSpacing="0">

                  <HeaderStyle BackColor="#00aaaa">
                  </HeaderStyle>

                </asp:DataGrid>
 
            </td>
         </tr>
 
      </table>
 
   </form>
 
</body>
</html>

Açıklamalar

Koleksiyonda belirtilen dizin konumuna DataGridColumnCollection türetilmiş bir DataGridColumnsütun nesnesi eklemek için bu yöntemi kullanın.

Denetim, DataGrid koleksiyonunun içeriğini Columns görünüm durumunda depolamaz. Bir sütunu dinamik olarak eklemek veya kaldırmak için, sayfa her yenilendiğinde sütunu program aracılığıyla eklemeniz veya kaldırmanız gerekir. Denetimin durumunu yeniden yükleyebilmesi ve kendisini yeniden oluşturabilmesi için önce DataGrid sütunu ekleyen veya kaldıran bir Page_Init işlev sağlayın. Aksi takdirde, koleksiyondaki Columns değişiklikler görüntülendiğinde denetime DataGrid yansıtılmaz.

Not

Program aracılığıyla denetim koleksiyonuna DataGrid sütun ekleyebilir veya kaldırabilirsinizColumns, ancak sütunları statik olarak listelemek ve ardından her sütunu görüntülemek veya gizlemek için özelliğini kullanmak Visible daha kolaydır.

Şunlara uygulanır

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