HyperLink.AddParsedSubObject(Object) Metoda

  • Reference

Definice

Obor názvů:
System.Web.UI.WebControls
Sestavení:
System.Web.dll

Upozorní ovládací prvek, že byl prvek analyzován a přidá prvek do HyperLink ovládacího prvku.

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)

Parametry

obj
Object

Jedná se Object o parsovaný prvek.

Příklady

Následující příklad kódu ukazuje, jak přepsat metodu AddParsedSubObject ve vlastním HyperLink ovládacím prvku serveru tak, aby vždy nastaví text vlastnost na parsovaný objekt text vlastnost, pokud parsovaný objekt je a Literalna prázdný řetězec jinak.

<%@ 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 HyperLink - AddParsedSubObject - C# Example</title>
    </head>
    <body>
        <form id="Form1" method="post" runat="server">
            <h3>Custom HyperLink - AddParsedSubObject - C# Example</h3>

            <aspSample:CustomHyperLinkAddParsedSubObject 
              id="HyperLink1" runat="server" Target="_blank"
              NavigateUrl="http://www.microsoft.com/"  
              ToolTip="Microsoft Web Site">www.microsoft.com
            </aspSample:CustomHyperLinkAddParsedSubObject>

        </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 HyperLink - AddParsedSubObject - VB.NET Example</title>
    </head>
    <body>
        <form id="Form1" method="post" runat="server">
            <h3>Custom HyperLink - AddParsedSubObject - VB.NET Example</h3>

            <aspSample:CustomHyperLinkAddParsedSubObject 
             id="HyperLink1" runat="server" Target="_blank"
             NavigateUrl="http://www.microsoft.com/"  
             ToolTip="Microsoft Web Site">www.microsoft.com
            </aspSample:CustomHyperLinkAddParsedSubObject>

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

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

namespace Samples.AspNet.CS.Controls
{
  [AspNetHostingPermission(SecurityAction.Demand, Level = AspNetHostingPermissionLevel.Minimal)]
  public sealed class CustomHyperLinkAddParsedSubObject : System.Web.UI.WebControls.HyperLink
  {
    protected override void AddParsedSubObject(object obj)
    {
      // If the server control contains any child controls.
      if (this.HasControls()) 
      {
        // Notify the base server control that an element, either XML or HTML, 
        // was parsed, and adds the element to the server control's 
        // ControlCollection object.
        base.AddParsedSubObject(obj);
      }
        // Else the server control doesn't contain any child controls.
      else 
      {
        // If the parsed element is a LiteralControl.
        if (obj is System.Web.UI.LiteralControl) 
        {
          // Set the server control's Text property to the parsed element's Text value.
          this.Text = ((System.Web.UI.LiteralControl)obj).Text;
        }
          // Else the parsed element is not a LiteralControl.
        else 
        {
          // If the server control has a value in the Text property.
          string currentText = this.Text;
          if (currentText.Length != 0) 
          {
            // Set the server control's Text property to an empty string.
            this.Text = System.String.Empty;

            // Notify the base server control that a new LiteralControl was parsed, 
            // and adds the element to the server control's ControlCollection object.
            base.AddParsedSubObject(new System.Web.UI.LiteralControl(currentText));
          }
          base.AddParsedSubObject(obj);
        }
      }
    }
  }
}

<AspNetHostingPermission(SecurityAction.Demand, Level:=AspNetHostingPermissionLevel.Minimal)> _
Public NotInheritable Class CustomHyperLinkAddParsedSubObject
    Inherits System.Web.UI.WebControls.HyperLink

    Protected Overrides Sub AddParsedSubObject(ByVal obj As Object)

        ' If the server control contains any child controls.
        If Me.HasControls() Then

            ' Notify the base server control that an element, either XML or HTML, 
            ' was parsed, and adds the element to the server control's 
            ' ControlCollection object.
            MyBase.AddParsedSubObject(obj)
            ' Else the server control doesn't contain any child controls.
        Else
            ' If the parsed element is a LiteralControl.
            If TypeOf obj Is System.Web.UI.LiteralControl Then

                ' Set the server control's Text property to the parsed element's Text value.
                Me.Text = CType(obj, System.Web.UI.LiteralControl).Text

                ' Else the parsed element is not a LiteralControl.
            Else
                ' If the server control has a value in the Text property.
                Dim currentText As String = Me.Text
                If currentText.Length <> 0 Then

                    ' Set the server control's Text property to an empty string.
                    Me.Text = System.String.Empty

                    ' Notify the base server control that a new LiteralControl was parsed, 
                    ' and adds the element to the server control's ControlCollection object.
                    MyBase.AddParsedSubObject(New System.Web.UI.LiteralControl(currentText))
                End If
                MyBase.AddParsedSubObject(obj)
            End If
        End If
    End Sub
End Class

Poznámky

Tato metoda se používá primárně ovládacími vývojáři při odvození vlastního ovládacího prvku z HyperLink třídy.

Pokud je vstupní objekt a LiteralControlHyperLink ovládací prvek nemá žádné podřízené ovládací prvky, pak se vstupní objekt použije k nastavení Text vlastnosti ovládacího prvku. AddParsedSubObject Jinak se volá metoda základní Control třídy a zadaný objekt se přidá do Controls kolekce.

Platí pro

Viz také