HtmlSelect.AddParsedSubObject(Object) Metod

Definition

Namnområde:
System.Web.UI.HtmlControls
Sammansättning:
System.Web.dll

Lägger till en parsad underordnad kontroll i HtmlSelect kontrollen.

protected:
 override void AddParsedSubObject(System::Object ^ obj);
protected override void AddParsedSubObject(object obj);
override this.AddParsedSubObject : obj -> unit
Protected Overrides Sub AddParsedSubObject (obj As Object)

Parametrar

obj
Object

Den parsade underordnade kontrollen som ska läggas till.

Implementeringar

AddParsedSubObject(Object)

Undantag

HttpException

Den underordnade kontroll som anges av parametern obj måste vara av typen ListItem.

Exempel

Följande kodexempel visar hur du åsidosätter AddParsedSubObject metoden i en anpassad serverkontroll så att den alltid kontrollerar att en instans av ListItem klassen läggs till i den valda objektsamlingen HtmlSelect .

<%@ 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 HtmlSelect - AddParsedSubObject - C# Example</title>
        <script runat="server">
      void HtmlInputButton1_ServerClick(Object sender, EventArgs e) 
      {
        if (HtmlSelect1.SelectedIndex >= 0)
        {
          if (HtmlSelect1.Multiple)
          {
            Div1.InnerHtml = "You selected:";
            for (int i=0; i<=HtmlSelect1.Items.Count - 1; i++)
            {
              if (HtmlSelect1.Items[i].Selected)
              {
                Div1.InnerHtml += "<br />    " + HtmlSelect1.Items[i].Value; 
              }     
            }
          }
          else
          {
            Div1.InnerHtml = "You selected " + HtmlSelect1.Value;
          }
        }
        else
        {
          Div1.InnerHtml = "You did not select an item.";
        }
      }
         </script>
    </head>
    <body>
        <form id="Form1" method="post" runat="server">
            <h3>Custom HtmlSelect - AddParsedSubObject - C# Example</h3>
            
            <p>
      <aspSample:CustomHtmlSelectAddParsedSubObject 
        id="HtmlSelect1" 
        name="HtmlSelect1"
        runat="server">
        <option value="Option1">Option1</option>
        <option value="Option2">Option2</option>
        <option value="Option3">Option3</option>
      </aspSample:CustomHtmlSelectAddParsedSubObject>
      </p>
      
      <p>
      <input 
        id="HtmlInputButton1" 
        runat="server" 
        type="button" 
        onserverclick="HtmlInputButton1_ServerClick"
        value="Select" 
        name="HtmlInputButton1" />  
      </p>
      
      <br />
      <div id="Div1" runat="server" 
        style="DISPLAY: inline; WIDTH: 256px; HEIGHT: 15px" />
       
        </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 HtmlSelect - AddParsedSubObject - VB.NET Example</title>
        <script runat="server">
      Sub HtmlInputButton1_ServerClick(sender As Object, e As EventArgs)
        If HtmlSelect1.SelectedIndex >= 0 Then
            If HtmlSelect1.Multiple = True Then
              Div1.InnerHtml = "You selected:"
              Dim i As Integer
              For i = 0 To HtmlSelect1.Items.Count - 1
                  If HtmlSelect1.Items(i).Selected = True Then
                    Div1.InnerHtml += "<br />    " & HtmlSelect1.Items(i).Value
                  End If
              Next i
            Else
              Div1.InnerHtml = "You selected " & HtmlSelect1.Value
            End If
        Else
            Div1.InnerHtml = "You did not select an item."
        End If
      End Sub
         </script>
    </head>
    <body>
        <form id="Form1" method="post" runat="server">
            <h3>Custom HtmlSelect - AddParsedSubObject - VB.NET Example</h3>
            
            <p>
      <aspSample:CustomHtmlSelectAddParsedSubObject 
        id="HtmlSelect1" 
        name="HtmlSelect1"
        runat="server">
        <option value="Option1">Option1</option>
        <option value="Option2">Option2</option>
        <option value="Option3">Option3</option>
      </aspSample:CustomHtmlSelectAddParsedSubObject>
      </p>
      
      <p>
      <input 
        id="HtmlInputButton1" 
        runat="server" 
        type="button" 
        onserverclick="HtmlInputButton1_ServerClick"
        value="Select" 
        name="HtmlInputButton1" />  
      </p>
      
      <br />
      <div id="Div1" runat="server" 
        style="DISPLAY: inline; WIDTH: 256px; HEIGHT: 15px" />
       
        </form>
    </body>
</html>

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

namespace Samples.AspNet.CS.Controls
{
    [AspNetHostingPermission(SecurityAction.Demand, Level = AspNetHostingPermissionLevel.Minimal)]
    public sealed class CustomHtmlSelectAddParsedSubObject : System.Web.UI.HtmlControls.HtmlSelect
    {
        protected override void AddParsedSubObject(object obj)
        {
            // If the object is a ListItem, then add the ListItem to the Items collection.
            if (obj is System.Web.UI.WebControls.ListItem)
            {
            Items.Add((System.Web.UI.WebControls.ListItem)obj);
            }
            else
            {
            throw new System.Web.HttpException("You cannot have a child control of type " + obj.GetType().Name.ToString());
            }
        }
    }
}

<AspNetHostingPermission(SecurityAction.Demand, Level:=AspNetHostingPermissionLevel.Minimal)> _
Public NotInheritable Class CustomHtmlSelectAddParsedSubObject
    Inherits System.Web.UI.HtmlControls.HtmlSelect

    Protected Overrides Sub AddParsedSubObject(ByVal obj As Object)

        ' If the object is a ListItem, then add the ListItem to the Items collection.
        If TypeOf obj Is System.Web.UI.WebControls.ListItem Then
            Items.Add(CType(obj, System.Web.UI.WebControls.ListItem))
        Else
            Throw New System.Web.HttpException("You cannot have a child control of type " + obj.GetType().Name.ToString())
        End If
    End Sub
End Class

Kommentarer

Metoden AddParsedSubObject används av ASP.NET för att lägga till parsade underordnade kontroller i kontrollen HtmlSelect.

Gäller för