次の方法で共有


DataGrid.Columns プロパティ

定義

DataGrid コントロールの列を表すオブジェクトのコレクションを取得します。

public:
 virtual property System::Web::UI::WebControls::DataGridColumnCollection ^ Columns { System::Web::UI::WebControls::DataGridColumnCollection ^ get(); };
[System.Web.UI.PersistenceMode(System.Web.UI.PersistenceMode.InnerProperty)]
public virtual System.Web.UI.WebControls.DataGridColumnCollection Columns { get; }
[<System.Web.UI.PersistenceMode(System.Web.UI.PersistenceMode.InnerProperty)>]
member this.Columns : System.Web.UI.WebControls.DataGridColumnCollection
Public Overridable ReadOnly Property Columns As DataGridColumnCollection

プロパティ値

DataGridColumnCollection コントロールの列を表すオブジェクトのコレクションを格納している DataGrid

属性

次のコード例では、 コレクションを使用 Columns して、コントロールに列を動的に追加する方法を DataGrid 示します。

<%@ 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>DataGrid Columns Example</title>
</head>
<body>
 
   <form id="form1" runat="server">
 
      <h3>DataGrid Columns 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>DataGrid Columns Example</title>
</head>
<body>
 
   <form id="form1" runat="server">
 
      <h3>DataGrid Columns 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="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 runat="server">
 
      ICollection CreateDataSource() 
      {
      
         // Create sample data for the DataGrid control.
         DataTable dt = new DataTable();
         DataRow dr;
 
         // Define the columns of the table.
         dt.Columns.Add(new DataColumn("IntegerValue", typeof(Int32)));
         dt.Columns.Add(new DataColumn("StringValue", typeof(string)));
         dt.Columns.Add(new DataColumn("CurrencyValue", typeof(double)));
 
         // Populate the table with sample values.
         for (int i = 0; i < 5; 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) 
      {
 
         // Load sample data only once, when the page is first loaded.
         if (!IsPostBack) 
         {
            ItemsGrid.DataSource = CreateDataSource();
            ItemsGrid.DataBind();
         }

      }

      void Button_Click(Object sender, EventArgs e) 
      {

         // Count the number of selected items in the DataGrid control.
         int count = 0;

         // Display the selected times.
         Message.Text = "You Selected: <br />";

         // Iterate through each item (row) in the DataGrid control and
         // determine whether it is selected.
         foreach (DataGridItem item in ItemsGrid.Items)
         {

            DetermineSelection(item, ref count);        

         }

         // If no items are selected, display the appropriate message.
         if (count == 0)
         {

            Message.Text = "No items selected";

         }

      }

      void DetermineSelection(DataGridItem item, ref int count)
      {

         // Retrieve the SelectCheckBox CheckBox control from the 
         // specified item (row) in the DataGrid control.
         CheckBox selection = (CheckBox)item.FindControl("SelectCheckBox");

         // If the item is selected, display the appropriate message and
         // increment the count of selected items.
         if (selection != null)
         {

           if (selection.Checked)
           {
              Message.Text += "- " + item.Cells[1].Text + "<br />";
              count++;
           }

         }    

      }

      void Check_Change(Object sender, EventArgs e)
      {

         // Show or hide the first column depending on the value of
         // the check box.
         if (ShowCheckBox.Checked)
         {
            ItemsGrid.Columns[0].Visible = true;
         }
         else
         {
            ItemsGrid.Columns[0].Visible = false;
         }

      }

   </script>
 
<head runat="server">
    <title>DataGridColumn Visible Example</title>
</head>
<body>
 
   <form id="form1" runat="server">
 
      <h3>DataGridColumn Visible Example</h3>

      Select whether to show or hide the first column.

      <br /><br />
 
      <b>Product List</b>
 
      <asp:DataGrid id="ItemsGrid"
           BorderColor="black"
           BorderWidth="1"
           CellPadding="3"
           ShowFooter="True"
           AutoGenerateColumns="False"
           runat="server">

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

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

         <Columns>

            <asp:BoundColumn DataField="IntegerValue"
                 Visible="True" 
                 HeaderText="Item"/>

            <asp:BoundColumn DataField="StringValue"
                 Visible="True"  
                 HeaderText="Description"/>

            <asp:BoundColumn DataField="CurrencyValue"
                 Visible="True"  
                 HeaderText="Price"
                 DataFormatString="{0:c}">

               <ItemStyle HorizontalAlign="Right">
               </ItemStyle>

            </asp:BoundColumn>

            <asp:TemplateColumn HeaderText="Select Item"
                 Visible="True" >

               <ItemTemplate>

                  <asp:CheckBox id="SelectCheckBox"
                       Text="Add to Cart"
                       Checked="False"
                       runat="server"/>

               </ItemTemplate>

            </asp:TemplateColumn>
 
         </Columns>  
 
      </asp:DataGrid>

      <br /><br />

      <asp:Button id="SubmitButton"
           Text="Submit"
           OnClick = "Button_Click"
           runat="server"/>

      <br /><br />

      <asp:Label id="Message"
           runat="server"/>

      <hr />

      <asp:CheckBox id="ShowCheckBox"
           Text="Show first column"
           AutoPostBack="True"
           OnCheckedChanged="Check_Change"
           Checked="True"
           runat="server"/>
 
   </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 runat="server">
 
      Function CreateDataSource() As ICollection 
      
         ' Create sample data for the DataGrid control.
         Dim dt As DataTable = New DataTable()
         Dim dr As DataRow
 
         ' Define the columns of the table.
         dt.Columns.Add(New DataColumn("IntegerValue", GetType(Int32)))
         dt.Columns.Add(New DataColumn("StringValue", GetType(string)))
         dt.Columns.Add(New DataColumn("CurrencyValue", GetType(double)))
 
         ' Populate the table with sample values.
         Dim i As Integer

         For i = 0 to 4 
        
            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 DataView = New DataView(dt)
         Return dv

      End Function
 
      Sub Page_Load(sender As Object, e As EventArgs) 
 
         ' Load sample data only once, when the page is first loaded.
         If Not IsPostBack Then 
  
            ItemsGrid.DataSource = CreateDataSource()
            ItemsGrid.DataBind()

         End If

      End Sub

      Sub Button_Click(sender As Object, e As EventArgs) 

         ' Count the number of selected items in the DataGrid control.
         Dim count As Integer = 0

         ' Display the selected times.
         Message.Text = "You Selected: <br />"

         ' Iterate through each item (row) in the DataGrid control and
         ' determine whether it is selected.
         Dim item As DataGridItem
 
         For Each item In ItemsGrid.Items

            DetermineSelection(item, count)        

         Next

         ' If no items are selected, display the appropriate message.
         If count = 0 Then

            Message.Text = "No items selected"

         End If

      End Sub

      Sub DetermineSelection(item As DataGridItem, ByRef count As Integer)

         ' Retrieve the SelectCheckBox CheckBox control from the 
         ' specified item (row) in the DataGrid control.
         Dim selection As CheckBox = _
             CType(item.FindControl("SelectCheckBox"), CheckBox)

         ' If the item is selected, display the appropriate message and
         ' increment the count of selected items.
         If Not selection Is Nothing Then

           If selection.Checked Then
           
              Message.Text &= "- " & item.Cells(1).Text & "<br />"
              count = count + 1
           
           End If

         End If    

      End Sub

      Sub Check_Change(sender As Object, e As EventArgs)

         ' Show or hide the first column depending on the value of
         ' the check box.
         If ShowCheckBox.Checked Then
        
            ItemsGrid.Columns(0).Visible = True
         
         Else
         
            ItemsGrid.Columns(0).Visible = False
         
         End If

      End Sub

   </script>
 
<head runat="server">
    <title>DataGridColumn Visible Example</title>
</head>
<body>
 
   <form id="form1" runat="server">
 
      <h3>DataGridColumn Visible Example</h3>

      Select whether to show or hide the first column.

      <br /><br />
 
      <b>Product List</b>
 
      <asp:DataGrid id="ItemsGrid"
           BorderColor="black"
           BorderWidth="1"
           CellPadding="3"
           ShowFooter="True"
           AutoGenerateColumns="False"
           runat="server">

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

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

         <Columns>

            <asp:BoundColumn DataField="IntegerValue"
                 Visible="True" 
                 HeaderText="Item"/>

            <asp:BoundColumn DataField="StringValue"
                 Visible="True"  
                 HeaderText="Description"/>

            <asp:BoundColumn DataField="CurrencyValue"
                 Visible="True"  
                 HeaderText="Price"
                 DataFormatString="{0:c}">

               <ItemStyle HorizontalAlign="Right">
               </ItemStyle>

            </asp:BoundColumn>

            <asp:TemplateColumn HeaderText="Select Item"
                 Visible="True" >

               <ItemTemplate>

                  <asp:CheckBox id="SelectCheckBox"
                       Text="Add to Cart"
                       Checked="False"
                       runat="server"/>

               </ItemTemplate>

            </asp:TemplateColumn>
 
         </Columns> 
 
      </asp:DataGrid>

      <br /><br />

      <asp:Button id="SubmitButton"
           Text="Submit"
           OnClick = "Button_Click"
           runat="server"/>

      <br /><br />

      <asp:Label id="Message"
           runat="server"/>

      <hr />

      <asp:CheckBox id="ShowCheckBox"
           Text="Show first column"
           AutoPostBack="True"
           OnCheckedChanged="Check_Change"
           Checked="True"
           runat="server"/>
 
   </form>
 
</body>
</html>

注釈

コントロール内の列のコレクションをプログラムで制御するには、このプロパティを DataGrid 使用します。 コレクションには Columns 、コントロールにレンダリングされる明示的に宣言された列が DataGrid 含まれています。

注意

明示的に宣言された列は、自動的に生成される列と組み合わせて使用できます。 両方を使用する場合、明示的に宣言された列が最初にレンダリングされ、その後に自動的に生成された列が表示されます。 自動的に生成された列はコレクションに Columns 追加されません。

コントロールに列が表示される DataGrid 順序は、列がコレクションに表示される順序によって Columns 制御されます。

次の表は、 クラスから DataGridColumn 派生し、コレクションで使用できるさまざまな列クラスを Columns 示しています。

列の型 説明
BoundColumn データ ソース内のフィールドにバインドされた列を表示します。 フィールドの各項目がテキストとして表示されます。 これは、コントロールの既定の列の DataGrid 種類です。
ButtonColumn 列の各項目のコマンド ボタンを表示します。 これにより、 や Remove ボタンなどのカスタム ボタン コントロールの列をAdd作成できます。
EditCommandColumn 列の各項目の編集コマンドを含む列を表示します。
HyperLinkColumn 列の各項目の内容をハイパーリンクとして表示します。 列の内容は、データ ソースまたは静的テキストのフィールドにバインドできます。
TemplateColumn 指定したテンプレートの後の列に各項目を表示します。 これにより、列にカスタム コントロールを指定できます。

注意

コレクションに列を Columns プログラムで追加することはできますが、列を静的に一覧表示してから、 プロパティを Visible 使用して列の表示と非表示を切り替える方が簡単です。

適用対象

こちらもご覧ください