CheckBoxList.IRepeatInfoUser.RenderItem Methode

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.

Eine Beschreibung dieses Elements finden Sie unter RenderItem(ListItemType, Int32, RepeatInfo, HtmlTextWriter).

 virtual void System.Web.UI.WebControls.IRepeatInfoUser.RenderItem(System::Web::UI::WebControls::ListItemType itemType, int repeatIndex, System::Web::UI::WebControls::RepeatInfo ^ repeatInfo, System::Web::UI::HtmlTextWriter ^ writer) = System::Web::UI::WebControls::IRepeatInfoUser::RenderItem;

void IRepeatInfoUser.RenderItem (System.Web.UI.WebControls.ListItemType itemType, int repeatIndex, System.Web.UI.WebControls.RepeatInfo repeatInfo, System.Web.UI.HtmlTextWriter writer);

abstract member System.Web.UI.WebControls.IRepeatInfoUser.RenderItem : System.Web.UI.WebControls.ListItemType * int * System.Web.UI.WebControls.RepeatInfo * System.Web.UI.HtmlTextWriter -> unit
override this.System.Web.UI.WebControls.IRepeatInfoUser.RenderItem : System.Web.UI.WebControls.ListItemType * int * System.Web.UI.WebControls.RepeatInfo * System.Web.UI.HtmlTextWriter -> unit

Sub RenderItem (itemType As ListItemType, repeatIndex As Integer, repeatInfo As RepeatInfo, writer As HtmlTextWriter) Implements IRepeatInfoUser.RenderItem

Parameter

itemType: ListItemType

Einer der ListItemType-Enumerationswerte.

repeatIndex: Int32

Ein Ordinalindex, der die Position des Elements im Listensteuerelement angibt.

repeatInfo: RepeatInfo

Ein RepeatInfo-Objekt, das die Informationen darstellt, die zum Rendern des Elements in der Liste verwendet werden.

writer: HtmlTextWriter

Ein HtmlTextWriter-Objekt, das den Ausgabestream für das Rendering von HTML-Inhalten auf dem Client darstellt.

Implementiert

RenderItem(ListItemType, Int32, RepeatInfo, HtmlTextWriter)

Beispiele

Im folgenden Codebeispiel wird veranschaulicht, wie die IRepeatInfoUser Schnittstellenelemente für ein benutzerdefiniertes CheckBoxList Objekt verwendet werden.

<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.CS.Controls" Assembly="Samples.AspNet.CS" %>
<%@ Page language="c#" %>
<!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" >
  <head>
    <title>Custom CheckBoxList - IRepeatInfoUser - C# Example</title>
  </head>
  <body>
    <form id="Form1" method="post" runat="server">
      <h3>Custom CheckBoxList - IRepeatInfoUser - C# Example</h3>
      <aspSample:CustomCheckBoxListIRepeatInfoUser
        id="CheckBoxList1" runat="server">
          <asp:ListItem Selected="True">Item 1</asp:ListItem>
          <asp:ListItem>Item 2</asp:ListItem>
          <asp:ListItem>Item 3</asp:ListItem>
          <asp:ListItem>Item 4</asp:ListItem>
          <asp:ListItem>Item 5</asp:ListItem>
          <asp:ListItem>Item 6</asp:ListItem>
      </aspSample:CustomCheckBoxListIRepeatInfoUser>
    </form>
  </body>
</html>

<%@ Page language="VB" %>
<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.VB.Controls" Assembly="Samples.AspNet.VB" %>
<!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" >
    <head>
        <title>Custom CheckBoxList - IRepeatInfoUser - VB.NET Example</title>
    </head>
    <body>
        <form id="Form1" method="post" runat="server">
            <h3>Custom CheckBoxList - IRepeatInfoUser - VB.NET Example</h3>
      <aspSample:CustomCheckBoxListIRepeatInfoUser id="CheckBoxList" runat="server">
                <asp:ListItem  Selected="True">Item 1</asp:ListItem>
                <asp:ListItem>Item 2</asp:ListItem>
                <asp:ListItem>Item 3</asp:ListItem>
                <asp:ListItem>Item 4</asp:ListItem>
                <asp:ListItem>Item 5</asp:ListItem>
                <asp:ListItem>Item 6</asp:ListItem>
            </aspSample:CustomCheckBoxListIRepeatInfoUser>
        </form>
    </body>
</html>

using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Security.Permissions;

namespace Samples.AspNet.CS.Controls
{
    [AspNetHostingPermission(SecurityAction.Demand, Level = 
        AspNetHostingPermissionLevel.Minimal)]
    public class CustomCheckBoxListIRepeatInfoUser : CheckBoxList
    {
        private bool hasFooter;
        private bool hasHeader;
        private bool hasSeparators;
        private int repeatedItemCount;
        private Style itemStyleItem;

        protected override void OnPreRender(System.EventArgs e)
        {
            // Call the base class's OnPreRender method
            base.OnPreRender(e);

            // Get a self-referencing IRepeatInfoUser object
            IRepeatInfoUser repeatInfoUser = (IRepeatInfoUser)this;

            // Get the IRepeatInfoUser members values.
            hasFooter = repeatInfoUser.HasFooter;
            hasHeader = repeatInfoUser.HasHeader;
            hasSeparators = repeatInfoUser.HasSeparators;
            repeatedItemCount = repeatInfoUser.RepeatedItemCount;
            itemStyleItem = repeatInfoUser.GetItemStyle(ListItemType.Item, 0);
        }

        protected override void Render(HtmlTextWriter writer)
        {
            // Create and setup a RepeatInfo class.
            RepeatInfo repeatInfo = new RepeatInfo();
            repeatInfo.RepeatColumns = 0;
            repeatInfo.RepeatDirection = RepeatDirection.Horizontal;
            repeatInfo.RepeatLayout = RepeatLayout.Table;

            // Get a self-referencing IRepeatInfoUser object
            IRepeatInfoUser repeatInfoUser = (IRepeatInfoUser)this;

            // Render the items using the above RepeatInfo class.
            repeatInfoUser.RenderItem(ListItemType.Item, 0, repeatInfo, writer);
            repeatInfoUser.RenderItem(ListItemType.Item, 1, repeatInfo, writer);
            repeatInfoUser.RenderItem(ListItemType.Item, 2, repeatInfo, writer);
            repeatInfoUser.RenderItem(ListItemType.Item, 3, repeatInfo, writer);
            repeatInfoUser.RenderItem(ListItemType.Item, 4, repeatInfo, writer);
            repeatInfoUser.RenderItem(ListItemType.Item, 5, repeatInfo, writer);
        }
    }
}

Imports System.Web
Imports System.Web.UI
Imports System.Web.UI.WebControls
Imports System.Security.Permissions

Namespace Samples.AspNet.VB.Controls

    <AspNetHostingPermission(SecurityAction.Demand, Level:=AspNetHostingPermissionLevel.Minimal)> _
    Public Class CustomCheckBoxListIRepeatInfoUser
        Inherits CheckBoxList

        Private _hasFooter As Boolean
        Private _hasHeader As Boolean
        Private _hasSeparators As Boolean
        Private _repeatedItemCount As Integer
        Private _itemStyleItem As Style

        Protected Overrides Sub OnPreRender(ByVal e As System.EventArgs)
            ' Call the base class's OnPreRender method
            MyBase.OnPreRender(e)

            ' Get a self-referencing IRepeatInfoUser object
            Dim repeatInfoUser As IRepeatInfoUser
            repeatInfoUser = CType(Me, IRepeatInfoUser)

            ' Get the IRepeatInfoUser member values.
            _hasFooter = repeatInfoUser.HasFooter
            _hasHeader = repeatInfoUser.HasHeader
            _hasSeparators = repeatInfoUser.HasSeparators
            _repeatedItemCount = repeatInfoUser.RepeatedItemCount
            _itemStyleItem = repeatInfoUser.GetItemStyle(ListItemType.Item, 0)
        End Sub

        Protected Overrides Sub Render(ByVal writer As System.Web.UI.HtmlTextWriter)
            ' Create and setup a RepeatInfo class.
            Dim repeatInfo As New RepeatInfo
            repeatInfo.RepeatColumns = 0
            repeatInfo.RepeatDirection = RepeatDirection.Horizontal
            repeatInfo.RepeatLayout = RepeatLayout.Table

            ' Get a self-referencing IRepeatInfoUser object
            Dim repeatInfoUser As IRepeatInfoUser
            repeatInfoUser = CType(Me, IRepeatInfoUser)

            ' Render the items using the above RepeatInfo and IRepeatInfoUser classes.
            repeatInfoUser.RenderItem(ListItemType.Item, 0, repeatInfo, writer)
            repeatInfoUser.RenderItem(ListItemType.Item, 1, repeatInfo, writer)
            repeatInfoUser.RenderItem(ListItemType.Item, 2, repeatInfo, writer)
            repeatInfoUser.RenderItem(ListItemType.Item, 3, repeatInfo, writer)
            repeatInfoUser.RenderItem(ListItemType.Item, 4, repeatInfo, writer)
            repeatInfoUser.RenderItem(ListItemType.Item, 5, repeatInfo, writer)
        End Sub
    End Class

End Namespace

Hinweise

Normalerweise sollten Sie die CheckBoxList.RenderItem Methode verwenden, um Elemente in einem CheckBoxList Objekt zu rendern.

Die IRepeatInfoUser.RenderItem Methode ist eine explizite Schnittstellenelementimplementierung. Er kann nur verwendet werden, wenn die CheckBoxList-Instanz in eine IRepeatInfoUser-Schnittstelle umgewandelt wird.

Hinweise für Vererber

Um eine benutzerdefinierte Implementierung für das Rendern von Elementen in einem CheckBoxList Objekt zu definieren, überschreiben Sie das RenderItem(ListItemType, Int32, RepeatInfo, HtmlTextWriter) Element. Die explizite Schnittstellenimplementierung ruft die RenderItem(ListItemType, Int32, RepeatInfo, HtmlTextWriter) Methode auf, um ein Element im Steuerelement zu rendern.

Gilt für