DataGrid.HeaderStyle Eigenschaft

Referenz

Definition

Namespace:: System.Web.UI.WebControls

Assembly:: System.Web.dll

Wichtig

Einige Informationen beziehen sich auf Vorabversionen, die vor dem Release ggf. grundlegend überarbeitet werden. Microsoft übernimmt hinsichtlich der hier bereitgestellten Informationen keine Gewährleistungen, seien sie ausdrücklich oder konkludent.

Ruft die Stileigenschaften des Headerzeilenbereichs im DataGrid-Steuerelement ab.

public:
 virtual property System::Web::UI::WebControls::TableItemStyle ^ HeaderStyle { System::Web::UI::WebControls::TableItemStyle ^ get(); };

[System.Web.UI.PersistenceMode(System.Web.UI.PersistenceMode.InnerProperty)]
public virtual System.Web.UI.WebControls.TableItemStyle HeaderStyle { get; }

[<System.Web.UI.PersistenceMode(System.Web.UI.PersistenceMode.InnerProperty)>]
member this.HeaderStyle : System.Web.UI.WebControls.TableItemStyle

Public Overridable ReadOnly Property HeaderStyle As TableItemStyle

Eigenschaftswert

TableItemStyle

Ein TableItemStyle-Objekt, das die Stileigenschaften des Headerzeilenbereichs im DataGrid-Steuerelement enthält. Der Standardwert ist ein leeres TableItemStyle-Objekt.

Attribute: PersistenceModeAttribute

Beispiele

Im folgenden Codebeispiel wird veranschaulicht, wie die HeaderStyle -Eigenschaft verwendet wird, um die Hintergrundfarbe des Überschriftenabschnitts festzulegen.

<%@ 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">
 
    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("DateTimeValue", typeof(string)));
       dt.Columns.Add(new DataColumn("BoolValue", typeof(bool)));
 
       for (int i = 0; i < 100; i++) {
          dr = dt.NewRow();
 
          dr[0] = i;
          dr[1] = "Item " + i.ToString();
          dr[2] = DateTime.Now.ToShortDateString();
          dr[3] = (i % 2 != 0) ? true : false;
 
          dt.Rows.Add(dr);
       }
 
       DataView dv = new DataView(dt);
       return dv;
    }
 
    void Page_Load(Object sender, EventArgs e) 
    {
       if (chk1.Checked)
          MyDataGrid.PagerStyle.Mode = PagerMode.NumericPages;
       else 
          MyDataGrid.PagerStyle.Mode = PagerMode.NextPrev;
 
       BindGrid();
    }
 
    void MyDataGrid_Page(Object sender, DataGridPageChangedEventArgs e)
   
    {
       MyDataGrid.CurrentPageIndex = e.NewPageIndex;
       BindGrid();
    }
 
    void BindGrid() 
    {
       MyDataGrid.DataSource = CreateDataSource();
       MyDataGrid.DataBind();
       ShowStats();
    }
 
    void ShowStats() 
    {
       lblEnabled.Text = "AllowPaging is " + MyDataGrid.AllowPaging;
       lblCurrentIndex.Text = "CurrentPageIndex is " + MyDataGrid.CurrentPageIndex;
       lblPageCount.Text = "PageCount is " + MyDataGrid.PageCount;
       lblPageSize.Text = "PageSize is " + MyDataGrid.PageSize;
    }
 
 
 </script>
 
 <head runat="server">
    <title>DataGrid Example</title>
</head>
<body>
 
    <h3>DataGrid Example</h3>
 
    <form id="form1" runat="server">
 
       <asp:DataGrid id="MyDataGrid" runat="server"
            AllowPaging="True"
            PageSize="10"            
            ShowFooter="true"
            OnPageIndexChanged="MyDataGrid_Page"
            BorderColor="black"
            BorderWidth="1"
            GridLines="Both"
            CellPadding="3"
            CellSpacing="0"
            Font-Names="Verdana"
            Font-Size="8pt">

          <PagerStyle Mode="NumericPages"
                      HorizontalAlign="Right">
          </PagerStyle>

          <HeaderStyle BackColor="#aaaadd">
          </HeaderStyle>

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

          <AlternatingItemStyle BackColor="#eeeeee">
          </AlternatingItemStyle>

       </asp:DataGrid>
 
       <br />
 
       <asp:Checkbox id="chk1" runat="server"
            Text="Show numeric page navigation buttons"
            Font-Names="Verdana"
            Font-Size="8pt"
            AutoPostBack="true"/>
 
       <br />
 
       <table style="background-color:#eeeeee; padding:6">
          <tr>
             <td style="display:inline">
                
 
                   <asp:Label id="lblEnabled" 
                        runat="server"/><br />
                   <asp:Label id="lblCurrentIndex" 
                        runat="server"/><br />
                   <asp:Label id="lblPageCount" 
                        runat="server"/><br />
                   <asp:Label id="lblPageSize" 
                        runat="server"/><br />
 
                
             </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">
 
    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("DateTimeValue", GetType(String)))
        dt.Columns.Add(New DataColumn("BoolValue", GetType(Boolean)))
        
        Dim i As Integer
        For i = 0 To 99
            dr = dt.NewRow()
            
            dr(0) = i
            dr(1) = "Item " + i.ToString()
            dr(2) = DateTime.Now.ToShortDateString()
            If i Mod 2 <> 0 Then
                dr(3) = True
            Else
                dr(3) = False
            End If
            
            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 chk1.Checked Then
            MyDataGrid.PagerStyle.Mode = PagerMode.NumericPages
        Else
            MyDataGrid.PagerStyle.Mode = PagerMode.NextPrev
        End If 
        BindGrid()
    End Sub 'Page_Load


    Sub MyDataGrid_Page(sender As Object, e As DataGridPageChangedEventArgs)
        
        MyDataGrid.CurrentPageIndex = e.NewPageIndex
        BindGrid()
    End Sub 'MyDataGrid_Page


    Sub BindGrid()
        MyDataGrid.DataSource = CreateDataSource()
        MyDataGrid.DataBind()
        ShowStats()
    End Sub 'BindGrid


    Sub ShowStats()
        lblEnabled.Text = "AllowPaging is " & MyDataGrid.AllowPaging
        lblCurrentIndex.Text = "CurrentPageIndex is " & MyDataGrid.CurrentPageIndex
        lblPageCount.Text = "PageCount is " & MyDataGrid.PageCount
        lblPageSize.Text = "PageSize is " & MyDataGrid.PageSize
    End Sub 'ShowStats
 
 
 </script>
 
 <head runat="server">
    <title>DataGrid Example</title>
</head>
<body>
 
    <h3>DataGrid Example</h3>
 
    <form id="form1" runat="server">
 
       <asp:DataGrid id="MyDataGrid" runat="server"
            AllowPaging="True"
            PageSize="10"            
            ShowFooter="true"
            OnPageIndexChanged="MyDataGrid_Page"
            BorderColor="black"
            BorderWidth="1"
            GridLines="Both"
            CellPadding="3"
            CellSpacing="0"
            Font-Names="Verdana"
            Font-Size="8pt">

          <PagerStyle Mode="NumericPages"
                      HorizontalAlign="Right">
          </PagerStyle>

          <HeaderStyle BackColor="#aaaadd">
          </HeaderStyle>

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

          <AlternatingItemStyle BackColor="#eeeeee">
          </AlternatingItemStyle>

       </asp:DataGrid>
 
       <br />
 
       <asp:Checkbox id="chk1" runat="server"
            Text="Show numeric page navigation buttons"
            Font-Names="Verdana"
            Font-Size="8pt"
            AutoPostBack="true"/>
 
       <br />
 
       <table style="background-color:#eeeeee; padding:6">
          <tr>
             <td style="display:inline">
                
 
                   <asp:Label id="lblEnabled" 
                        runat="server"/><br />
                   <asp:Label id="lblCurrentIndex" 
                        runat="server"/><br />
                   <asp:Label id="lblPageCount" 
                        runat="server"/><br />
                   <asp:Label id="lblPageSize" 
                        runat="server"/><br />
 
                
             </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 = "Not 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 Selection_Change(Object sender, EventArgs e)
      {

         // Set the background color for the heading and footer sections of
         // the DataGrid control.
         ItemsGrid.HeaderStyle.BackColor = System.Drawing.Color.FromName(List.SelectedItem.Value);
         ItemsGrid.FooterStyle.BackColor = System.Drawing.Color.FromName(List.SelectedItem.Value);

      }

   </script>
 
<head runat="server">
    <title>DataGrid HeaderStyle and FooterStyle Example</title>
</head>
<body>
 
   <form id="form1" runat="server">
 
      <h3>DataGrid HeaderStyle and FooterStyle Example</h3>

      Select a backcolor for the header and footer sections.

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

         <HeaderStyle BackColor="White">
         </HeaderStyle>

         <FooterStyle BackColor="White">
         </FooterStyle>

         <Columns>

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

            <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="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 />

      Header and footer backcolor: <br /> 

      <asp:DropDownList id="List"
           AutoPostBack="True"
           OnSelectedIndexChanged="Selection_Change"
           runat="server">

         <asp:ListItem Selected="True" Value="White"> White </asp:ListItem>
         <asp:ListItem Value="Silver"> Silver </asp:ListItem>
         <asp:ListItem Value="DarkGray"> Dark Gray </asp:ListItem>
         <asp:ListItem Value="Khaki"> Khaki </asp:ListItem>
         <asp:ListItem Value="DarkKhaki"> Dark Khaki </asp:ListItem>

      </asp:DropDownList>
 
   </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 = "Not 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 Selection_Change(sender As Object, e As EventArgs)

         ' Set the background color for the heading and footer sections of
         ' the DataGrid control.
         ItemsGrid.HeaderStyle.BackColor = System.Drawing.Color.FromName(List.SelectedItem.Value)
         ItemsGrid.FooterStyle.BackColor = System.Drawing.Color.FromName(List.SelectedItem.Value)

      End Sub

   </script>
 
<head runat="server">
    <title>DataGrid HeaderStyle and FooterStyle Example</title>
</head>
<body>
 
   <form id="form1" runat="server">
 
      <h3>DataGrid HeaderStyle and FooterStyle Example</h3>

      Select a backcolor for the header and footer sections.

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

         <HeaderStyle BackColor="White">
         </HeaderStyle>

         <FooterStyle BackColor="White">
         </FooterStyle>

         <Columns>

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

            <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="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 />

      Header and footer backcolor: <br /> 

      <asp:DropDownList id="List"
           AutoPostBack="True"
           OnSelectedIndexChanged="Selection_Change"
           runat="server">

         <asp:ListItem Selected="True" Value="White"> White </asp:ListItem>
         <asp:ListItem Value="Silver"> Silver </asp:ListItem>
         <asp:ListItem Value="DarkGray"> Dark Gray </asp:ListItem>
         <asp:ListItem Value="Khaki"> Khaki </asp:ListItem>
         <asp:ListItem Value="DarkKhaki"> Dark Khaki </asp:ListItem>

      </asp:DropDownList>
 
   </form>
 
</body>
</html>

Hinweise

Verwenden Sie diese Eigenschaft, um eine benutzerdefinierte Formatvorlage für den Überschriftenabschnitt des DataGrid Steuerelements bereitzustellen. Allgemeine Stilattribute, die angepasst werden können, sind forecolor, backcolor, font und content alignment in the cell. Das Bereitstellen eines anderen Stils verbessert das Erscheinungsbild des DataGrid Steuerelements.

Die HeaderStyle -Eigenschaft des DataGrid -Steuerelements erbt die Stileinstellungen der ControlStyle -Eigenschaft. Wenn Sie beispielsweise eine rote Schriftart für die ControlStyle Eigenschaft angeben, weist die HeaderStyle Eigenschaft auch eine rote Schriftart auf. Auf diese Weise können Sie eine gemeinsame Darstellung für das Steuerelement bereitstellen, indem Sie eine einzelne Stileigenschaft festlegen. Sie können die geerbten Stileinstellungen überschreiben, indem Sie die HeaderStyle -Eigenschaft festlegen. Sie können beispielsweise eine blaue Schriftart für die HeaderStyle -Eigenschaft angeben und die in der ControlStyle -Eigenschaft angegebene rote Schriftart überschreiben.

Um eine benutzerdefinierte Formatvorlage für den Überschriftenabschnitt anzugeben, platzieren Sie die <HeaderStyle> Tags zwischen den öffnenden und schließenden Tags des DataGrid Steuerelements. Anschließend können Sie die Stilattribute innerhalb des öffnenden <HeaderStyle> Tags auflisten.

Hinweis

Die ShowHeader -Eigenschaft muss auf true festgelegt werden, damit diese Eigenschaft sichtbar ist.

Gilt für:

Freigeben über