DataGrid.HeaderStyle DataGrid.HeaderStyle DataGrid.HeaderStyle DataGrid.HeaderStyle Property

Definizione

Ottiene le proprietà di stile della sezione dell'intestazione nel controllo DataGrid.Gets the style properties of the heading section in the DataGrid control.

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; }
member this.HeaderStyle : System.Web.UI.WebControls.TableItemStyle
Public Overridable ReadOnly Property HeaderStyle As TableItemStyle

Valore della proprietà

Un oggetto TableItemStyle che contiene le proprietà di stile della sezione dell'intestazione nel controllo DataGrid.A TableItemStyle object that contains the style properties of the heading section in the DataGrid control. Il valore predefinito è un oggetto TableItemStyle vuoto.The default value is an empty TableItemStyle object.

Esempi

Esempio di codice seguente viene illustrato come utilizzare il HeaderStyle proprietà da impostare il colore di sfondo della sezione dell'intestazione.The following code example demonstrates how to use the HeaderStyle property to set the background color of the heading section.

<%@ 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>

Commenti

Usare questa proprietà per fornire uno stile personalizzato per la sezione dell'intestazione di DataGrid controllo.Use this property to provide a custom style for the heading section of the DataGrid control. Gli attributi di stile comune che possono essere regolati includono forecolor, colore di sfondo, tipo di carattere e l'allineamento del contenuto all'interno della cella.Common style attributes that can be adjusted include forecolor, backcolor, font, and content alignment within the cell. Utilizzo di uno stile diverso di contribuire a migliorare l'aspetto del DataGrid controllo.Providing a different style enhances the appearance of the DataGrid control.

Il HeaderStyle proprietà del DataGrid controllo eredita le impostazioni di stile del ControlStyle proprietà.The HeaderStyle property of the DataGrid control inherits the style settings of the ControlStyle property. Ad esempio, se si specifica un carattere di colore rosso per il ControlStyle proprietà, il HeaderStyle anche proprietà avrà un carattere di colore rosso.For example, if you specify a red font for the ControlStyle property, the HeaderStyle property will also have a red font. In questo modo è possibile fornire un aspetto comune per il controllo impostando una singola proprietà di stile.This allows you to provide a common appearance for the control by setting a single style property. È possibile ignorare le impostazioni di stile ereditato impostando il HeaderStyle proprietà.You can override the inherited style settings by setting the HeaderStyle property. Ad esempio, è possibile specificare un carattere di colore blu per i HeaderStyle proprietà, viene sottoposto a override il tipo di carattere rosso specificato nella ControlStyle proprietà.For example, you can specify a blue font for the HeaderStyle property, overriding the red font specified in the ControlStyle property.

Per specificare uno stile personalizzato per la sezione di intestazione, posizionare il <HeaderStyle> tra i tag di apertura e chiusura del tag di DataGrid controllo.To specify a custom style for the heading section, place the <HeaderStyle> tags between the opening and closing tags of the DataGrid control. È quindi possibile elencare gli attributi di stile all'interno del tag <HeaderStyle> tag.You can then list the style attributes within the opening <HeaderStyle> tag.

Nota

Il ShowHeader proprietà deve essere impostata su true per questa proprietà sia visibile.The ShowHeader property must be set to true for this property to be visible.

Si applica a

Vedi anche