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HtmlTable.RenderChildren(HtmlTextWriter) Method

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Definition

Namespace:
System.Web.UI.HtmlControls
Assembly:
System.Web.dll

Renders the HtmlTable control's child controls to the specified HtmlTextWriter object.

protected:
 override void RenderChildren(System::Web::UI::HtmlTextWriter ^ writer);
protected public:
 override void RenderChildren(System::Web::UI::HtmlTextWriter ^ writer);
protected override void RenderChildren (System.Web.UI.HtmlTextWriter writer);
protected internal override void RenderChildren (System.Web.UI.HtmlTextWriter writer);
override this.RenderChildren : System.Web.UI.HtmlTextWriter -> unit
Protected Overrides Sub RenderChildren (writer As HtmlTextWriter)
Protected Friend Overrides Sub RenderChildren (writer As HtmlTextWriter)

Parameters

writer
HtmlTextWriter

The HtmlTextWriter that receives the rendered content.

Examples

The following code example demonstrates how to override the RenderChildren method in a custom server control so that a new table row is appended to the HtmlTable control.

<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.CS.Controls" Assembly="Samples.AspNet.CS" %>
<%@ Page Language="C#" AutoEventWireup="True" %>
<!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 HtmlTable - RenderChildren Example</title>
    </head>
    <body>
        <form id="Form1" 
          method="post" 
          runat="server">
            <h3>Custom HtmlTable - RenderChildren Example</h3>
      
      <aspSample:CustomHtmlTableRenderChildren 
        id="HtmlTable1" 
        name="HtmlTable1" 
        runat="server" 
        border="1"
        cellSpacing="0" 
        cellPadding="5">
        <tr>
          <td>1,1</td>
          <td>1,2</td>
          <td>1,3</td>
        </tr>
        <tr>
          <td>2,1</td>
          <td>2,2</td>
          <td>2,3</td>
        </tr>
        <tr>
          <td>3,1</td>
          <td>3,2</td>
          <td>3,3</td>
        </tr>
      </aspSample:CustomHtmlTableRenderChildren>

        </form>
    </body>
</html>

<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.VB.Controls" Assembly="Samples.AspNet.VB" %>
<%@ Page Language="VB" AutoEventWireup="True" %>
<!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 HtmlTable - RenderChildren Example</title>
    </head>
    <body>
        <form id="Form1" 
          method="post" 
          runat="server">
            <h3>Custom HtmlTable - RenderChildren Example</h3>
      
      <aspSample:CustomHtmlTableRenderChildren 
        id="HtmlTable1" 
        name="HtmlTable1" 
        runat="server" 
        border="1"
        cellSpacing="0" 
        cellPadding="5">
        <tr>
          <td>1,1</td>
          <td>1,2</td>
          <td>1,3</td>
        </tr>
        <tr>
          <td>2,1</td>
          <td>2,2</td>
          <td>2,3</td>
        </tr>
        <tr>
          <td>3,1</td>
          <td>3,2</td>
          <td>3,3</td>
        </tr>
      </aspSample:CustomHtmlTableRenderChildren>

        </form>
    </body>
</html>

using System.Web;
using System.Security.Permissions;

namespace Samples.AspNet.CS.Controls
{
    [AspNetHostingPermission(SecurityAction.Demand, Level = AspNetHostingPermissionLevel.Minimal)]
    public sealed class CustomHtmlTableRenderChildren : System.Web.UI.HtmlControls.HtmlTable
    {
        protected override void RenderChildren(System.Web.UI.HtmlTextWriter writer)
        {
            // Call the base class's RenderChildren method.
            base.RenderChildren(writer);
            
            // Write out a new table row.
            writer.RenderBeginTag(System.Web.UI.HtmlTextWriterTag.Tr);
            writer.RenderBeginTag(System.Web.UI.HtmlTextWriterTag.Td);
            writer.Write("4,1");
            writer.RenderEndTag();
            writer.RenderBeginTag(System.Web.UI.HtmlTextWriterTag.Td);
            writer.Write("4,2");
            writer.RenderEndTag();
            writer.RenderBeginTag(System.Web.UI.HtmlTextWriterTag.Td);
            writer.Write("4,3");
            writer.RenderEndTag();
            writer.RenderEndTag();
        }
    }
}

Imports System.Web
Imports System.Security.Permissions

Namespace Samples.AspNet.VB.Controls
    <AspNetHostingPermission(SecurityAction.Demand, Level:=AspNetHostingPermissionLevel.Minimal)> _
    Public NotInheritable Class CustomHtmlTableRenderChildren
        Inherits System.Web.UI.HtmlControls.HtmlTable

        Protected Overrides Sub RenderChildren(ByVal writer As System.Web.UI.HtmlTextWriter)

            ' Call the base class's RenderChildren method.
            MyBase.RenderChildren(writer)

            ' Write out a new table row.
            writer.RenderBeginTag(System.Web.UI.HtmlTextWriterTag.Tr)
            writer.RenderBeginTag(System.Web.UI.HtmlTextWriterTag.Td)
            writer.Write("4,1")
            writer.RenderEndTag()
            writer.RenderBeginTag(System.Web.UI.HtmlTextWriterTag.Td)
            writer.Write("4,2")
            writer.RenderEndTag()
            writer.RenderBeginTag(System.Web.UI.HtmlTextWriterTag.Td)
            writer.Write("4,3")
            writer.RenderEndTag()
            writer.RenderEndTag()
        End Sub
    End Class
End Namespace

Remarks

The RenderChildren method provides additional formatting before and after calling the base class's Control.RenderChildren method. The additional formatting makes the rendered HTML of the HtmlTable control easier to read by inserting a line return and indenting before rendering the HtmlTable control's child controls.

The RenderChildren method is used primarily by control developers extending the functionality of the HtmlTable control.

Applies to

See also