次の方法で共有

DataGridColumn.HeaderText プロパティ

  • リファレンス

定義

名前空間:
System.Web.UI.WebControls
アセンブリ:
System.Web.dll

列のヘッダー セクションに表示されるテキストを取得または設定します。

public:
 virtual property System::String ^ HeaderText { System::String ^ get(); void set(System::String ^ value); };
public virtual string HeaderText { get; set; }
member this.HeaderText : string with get, set
Public Overridable Property HeaderText As String

プロパティ値

String

列のヘッダー セクションに表示されるテキスト。 既定値は Empty です。

例

次のコード例では、 プロパティを使用して、列の HeaderText ヘッダー セクションのテキストを指定する方法を示します。


<%@ 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 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)));
         dt.Columns.Add(new DataColumn("BooleanValue", typeof(bool)));
 
         // 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);
            dr[3] = false;
 
            dt.Rows.Add(dr);
         }

         // To persist the data source between posts to the server, store
         // it in session state.  
         Session["Source"] = dt;
 
         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) 
         {
            // Make sure to set the header text before binding the data to 
            // the DataGrid control; otherwise, the change will not appear 
            // until the next time the page is refreshed.
            ItemsGrid.Columns[0].HeaderText = "Item";

            ItemsGrid.DataSource = CreateDataSource();
            ItemsGrid.DataBind();
         }

      }

      void Button_Click(Object sender, EventArgs e) 
      {

         double subtotal = 0.0;

         // Update the data source with the user's selection and 
         // calculate the subtotal.
         DataTable dt = UpdateSource(ref subtotal);

         // Display the subtotal in the footer section of the third column.
         ItemsGrid.Columns[2].FooterText = 
             "Subtotal: " + subtotal.ToString("c");

         // Create a DataView and bind it to the DataGrid control.
         DataView dv = new DataView(dt);
         ItemsGrid.DataSource = dv;
         ItemsGrid.DataBind();

      }

      DataTable UpdateSource(ref double subtotal)
      {

         // Retrieve the data table from session state.
         DataTable dt = (DataTable)Session["Source"];

         // Iterate through the Items collection and update the data source
         // with the user's selections. If an item is selected, add the
         // amount of the item to the subtotal.
         foreach (DataGridItem item in ItemsGrid.Items)
         {

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

            if (selection != null)
            {

               // Update the BooleanValue field with the value of the check box.
               dt.Rows[item.ItemIndex][3] = selection.Checked;

               // Add the value of the item to the subtotal if the item is 
               // selected.
               if (selection.Checked)
               {
                  subtotal += 
                      Convert.ToDouble(item.Cells[2].Text.Substring(1));
               }

            }

         }

         // Save the data source.
         Session["Source"] = dt;

         return dt;

      }

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

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

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

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

            </asp:BoundColumn>

            <asp:TemplateColumn HeaderText="Select Item">

               <ItemTemplate>

                  <asp:CheckBox id="SelectCheckBox"
                       Text="Add to Cart"
                       Checked='<%# DataBinder.Eval(Container.DataItem, "BooleanValue") %>'
                       runat="server"/>

               </ItemTemplate>

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

      <br /><br />

      <asp:Button id="SubmitButton"
           Text="Submit"
           OnClick = "Button_Click"
           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)))
         dt.Columns.Add(new DataColumn("BooleanValue", GetType(Boolean)))
 
         ' 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)
            dr(3) = False
 
            dt.Rows.Add(dr)
         
         Next i

         ' To persist the data source between posts to the server, store
         ' it in session state.  
         Session("Source") = dt
 
         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 
         
            ' Make sure to set the header text before binding the data to 
            ' the DataGrid control; otherwise, the change will not appear 
            ' until the next time the page is refreshed.
            ItemsGrid.Columns(0).HeaderText = "Item"

            ItemsGrid.DataSource = CreateDataSource()
            ItemsGrid.DataBind()
        
         End If

      End Sub

      Sub Button_Click(sender As Object, e As EventArgs) 

         Dim subtotal As Double = 0.0

         ' Update the data source with the user's selection and 
         ' calculate the subtotal.
         Dim dt As DataTable = UpdateSource(subtotal)

         ' Display the subtotal in the footer section of the third column.
         ItemsGrid.Columns(2).FooterText = _
             "Subtotal: " & subtotal.ToString("c")

         ' Create a DataView and bind it to the DataGrid control.
         Dim dv As DataView = New DataView(dt)
         ItemsGrid.DataSource = dv
         ItemsGrid.DataBind()

      End Sub

      Function UpdateSource(ByRef subtotal As Double) As DataTable 

         ' Retrieve the data table from session state.
         Dim dt As DataTable = CType(Session("Source"), DataTable)
         Dim item As DataGridItem 

         ' Iterate through the Items collection and update the data source
         ' with the user's selections. If an item is selected, add the
         ' amount of the item to the subtotal.
         For Each item in ItemsGrid.Items

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

            If Not selection Is Nothing

               ' Update the BooleanValue field with the value of the check box.
               dt.Rows(item.ItemIndex)(3) = selection.Checked

               ' Add the value of the item to the subtotal if the item is 
               ' selected.
               If selection.Checked Then
           
                  subtotal += _
                      Convert.ToDouble(item.Cells(2).Text.Substring(1))

               End If

            End If

         Next

         ' Save the data source.
         Session("Source") = dt

         Return dt

      End Function

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

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

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

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

            </asp:BoundColumn>

            <asp:TemplateColumn HeaderText="Select Item">

               <ItemTemplate>

                  <asp:CheckBox id="SelectCheckBox"
                       Text="Add to Cart"
                       Checked='<%# DataBinder.Eval(Container.DataItem, "BooleanValue") %>'
                       runat="server"/>

               </ItemTemplate>

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

      <br /><br />

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

注釈

プロパティを HeaderText 使用して、列のヘッダー セクションに表示されるテキストを指定または決定します。 列のヘッダー セクションにテキストの代わりに画像を表示する場合は、このプロパティの代わりに プロパティを HeaderImageUrl 設定します。

注意事項

テキストは、列のヘッダー セクションに表示される前に HTML エンコードされません。 これにより、テキスト内の HTML タグ内にスクリプトを埋め込むことができます。 このプロパティがユーザー入力を使用して動的に設定されている場合は、セキュリティの脆弱性を軽減するために値を検証してください。

適用対象

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