ControlBuilderAttribute クラス

.NET Framework クラス ライブラリ リファレンス

ControlBuilderAttribute クラス

ASP.NET パーサー内でカスタム コントロールを作成する ControlBuilder クラスを指定します。このクラスは継承できません。

名前空間: System.Web.UI
アセンブリ: System.Web (system.web.dll 内)
構文

Visual Basic (宣言)

<AttributeUsageAttribute(AttributeTargets.Class)> _
Public NotInheritable Class
 ControlBuilderAttribute
    Inherits Attribute

Visual Basic (使用法)

Dim instance As ControlBuilderAttribute

C#

[AttributeUsageAttribute(AttributeTargets.Class)] 
public sealed class ControlBuilderAttribute
 : Attribute

C++

[AttributeUsageAttribute(AttributeTargets::Class)] 
public ref class ControlBuilderAttribute sealed
 : public Attribute

J#

/** @attribute AttributeUsageAttribute(AttributeTargets.Class) */ 
public final class ControlBuilderAttribute
 extends Attribute

JScript

AttributeUsageAttribute(AttributeTargets.Class) 
public final class ControlBuilderAttribute
 extends Attribute

解説

この属性は、次のコードに示すように、カスタム コントロールの作成に使用するビルダの Type を指定します。

[ControlBuilderAttribute(typeof(ControlBuilderType))]

使用例

次のコード例では、実行時に定義された SelectedIndex 値と Message 値に基づいてメッセージを表示するために使用する、カスタマイズされた選択リストを作成します。実行可能ファイルの作成には、次のコマンド ラインを使用します。

Visual Basic

vbc /r:System.dll /r:System.Web.dll /r:System.Drawing.dll /t:library /out:myWebAppPath/Bin/vb_MyControlBuilderAtt.dll
 ControlBuilderAtt.vb

C#

csc /t:library /out:myWebAppPath/Bin/cs_MyControlBuilderAtt.dll ControlBuilderAtt.cs

Visual Basic

'File name: controlBuilderAttribute.vb.

Imports System
Imports System.Web
Imports System.Web.UI
Imports System.Web.UI.WebControls
Imports System.Collections



Namespace CustomControls

Public Class MyVB_Item: Inherits
 Control
      
      Private _message As String
      
      Public Property Message() As
 String
         Get
            Return _message
         End Get
         Set
            _message = value
         End Set
      End Property
   End Class 'MyVB_Item
   
   Public Class VB_CustomParseControlBuilder:
 Inherits ControlBuilder

      <System.Security.Permissions.PermissionSetAttribute(System.Security.Permissions.SecurityAction.Demand,
 Name:="FullTrust")>  _
      Public Overrides Function
 GetChildControlType(TagName As String, attributes
 As IDictionary) As Type
          If (TagName = "customitem")
  Then
            Return GetType(CustomControls.MyVB_Item)
         End If
         Return Nothing
      End Function 'GetChildControlType
   End Class 'CustomParseControlBuilder
   
   <ControlBuilderAttribute(GetType(VB_CustomParseControlBuilder))>
  Public Class MyVB_CustomParse: Inherits
 Control
      
      Private _items As New
 ArrayList
      Private _selectedIndex As Integer
 = 0
      
      
      Public Property SelectedIndex() As
 Integer
         Get
            Return _selectedIndex
         End Get
         Set
            _selectedIndex = value
         End Set
      End Property
      
      <System.Security.Permissions.PermissionSetAttribute(System.Security.Permissions.SecurityAction.Demand,
 Name:="FullTrust")> _
      Protected Overrides Sub
 AddParsedSubObject(obj As Object)
         If TypeOf obj Is
 MyVB_Item Then
            _items.Add(obj)
         End If
      End Sub 'AddParsedSubObject
      
      <System.Security.Permissions.PermissionSetAttribute(System.Security.Permissions.SecurityAction.Demand,
 Name:="FullTrust")> _
      Protected Overrides Sub
 Render(output As HtmlTextWriter)        
        output.Write(("<span style='background-color:aqua; color:red;
 font:8pt tahoma, verdana;'><b>" + CType(_items(SelectedIndex), MyVB_Item).Message
 + "</b></span>"))
      End Sub 'Render
   End Class 'MyVB_CustomParse
 
   
End Namespace 'CustomControls

C#

/* File name: controlBuilderAttribute.cs. */

using System;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Collections;


namespace CustomControls

{
  public class MyCS_Item : Control 
  /* Class name: MyCS_Item. 
   * Defines the child control class.
   */
    {

      private String _message;

      public String Message 
      {
        get 
        {
          return _message;
        }
        set 
        {
           _message = value;
        }
     }
    }


    public class CustomParseControlBuilder
 : ControlBuilder 
    /* Class name: CustomParserControlBuilder.
     * Defines the functions and data to be used in building custom
 controls. 
     * This class is referenced using the ControlBuilderAttribute
 class. See class below.
     */
    {
      [System.Security.Permissions.PermissionSet(System.Security.Permissions.SecurityAction.Demand,
 Name="FullTrust")] 
      public override Type GetChildControlType(String tagName,
 IDictionary attributes) 
      {
        if (String.Compare(tagName, "customitem", true)
 == 0) 
        {
           return typeof(MyCS_Item);
        }
        return null;
      }
    }


    [ 
       ControlBuilderAttribute(typeof(CustomParseControlBuilder)) 
    ]
    public class MyCS_CustomParse : Control
 
    /* Class name: MyCS_CustomParse.
     * Performs custom parsing of a MyCS_CustomParse control type 
     * child control. 
     * If the child control is of the allowed type, it is added to an 
     * array list. This list is accessed, using the container
 control attribute 
     * SelectedIndex, to obtain the related child control Message attribute to be
 displayed.
     */
    {

       private ArrayList _items         = new
 ArrayList();
       private int       _selectedIndex = 0;

       public int SelectedIndex 
       { 
           get 
           {
              return _selectedIndex;
           }
           set 
           {
              _selectedIndex = value;
           }
       }

       [System.Security.Permissions.PermissionSet(System.Security.Permissions.SecurityAction.Demand,
 Name="FullTrust")] 
       protected override void AddParsedSubObject(Object
 obj) 
       /* Function name: AddParsedSubObject.
        * Updates the array list with the allowed child objects.
        * This function is called during the parsing of the child controls and 
        * after the GetChildControlType function defined in the
 associated control 
        * builder class.
        */
       {
          if (obj is MyCS_Item) 
         {
              _items.Add(obj);
           }
       }

       [System.Security.Permissions.PermissionSet(System.Security.Permissions.SecurityAction.Demand,
 Name="FullTrust")] 
       protected override void Render(HtmlTextWriter
 output) 
       /* Function name: Render.
        * Establishes the rules to render the built control. In this
 case, a message is
        * rendered that is a function of the parent control SelectedIndex attribute
 and 
        * the related child Message attribute.
        */
       {
          if (SelectedIndex < _items.Count) 
         {
              output.Write("<span style='background-color:aqua; color:red;
 font:8pt tahoma, verdana;'><b>" +
              ((MyCS_Item) _items[SelectedIndex]).Message + "</b></span>"
 );
         }
       }
    }    
}

J#

package CustomControls;

/* File name: controlBuilderAttribute.jsl. */
import System.*;
import System.Web.*;
import System.Web.UI.*;
import System.Web.UI.WebControls.*;
import System.Collections.*;

public class MyJSL_Item extends Control
{
    /* Class name: MyJSL_Item. 
       Defines the child control class.
     */
    private String _message;
    /** @property 
     */
    public String get_Message()
    {
        return _message;
    } //get_Message

    /** @property 
     */
    public void set_Message(String value)
    {
        _message = value;
    } //set_Message
} //MyJSL_Item

public class CustomParseControlBuilder extends
 ControlBuilder
{
    /* Class name: CustomParserControlBuilder.
       Defines the functions and data to be used in building custom
 controls. 
       This class is referenced using the ControlBuilderAttribute
 class.
       See class below.
     */
    public Type GetChildControlType(String tagName, IDictionary
 attributes)
    {
        if (String.Compare(tagName, "customitem", true)
 == 0) {
            return MyJSL_Item.class.ToType();
        }
        return null;
    } //GetChildControlType
} //CustomParseControlBuilder

/** @attribute ControlBuilderAttribute(CustomParseControlBuilder.class)
 */
public class MyJSL_CustomParse extends Control
{
    /* Class name: MyJSL_CustomParse.
       Performs custom parsing of a MyJSL_CustomParse control type 
       child control. 
       If the child control is of the allowed type, it is added to an 
       array list. This list is accessed, using the container
 control attribute 
       SelectedIndex, to obtain the related child control Message attribute
       to be displayed.
     */
    private ArrayList _items = new ArrayList();
    private int _selectedIndex = 0;

    /** @property 
     */
    public int get_SelectedIndex()
    {
        return _selectedIndex;
    } //get_SelectedIndex

    /** @property 
     */
    public void set_SelectedIndex(int
 value)
    {
        _selectedIndex = value;
    } //set_SelectedIndex

    protected void AddParsedSubObject(Object
 obj)
    {
        /* Function name: AddParsedSubObject.
           Updates the array list with the allowed child objects.
           This function is called during the parsing of the child controls and 
           after the GetChildControlType function defined in the
 associated control 
           builder class.
        */
        if (obj instanceof MyJSL_Item) {
            _items.Add(obj);
        }
    } //AddParsedSubObject

    protected void Render(HtmlTextWriter output)
    {
        /* Function name: Render.
           Establishes the rules to render the built control. In this
 case,
           a message is rendered that is a function of the parent control
           SelectedIndex attribute and the related child Message attribute.
        */
        if (get_SelectedIndex() < _items.get_Count()) {
            output.Write("<span style='background-color:aqua; color:red;"
                + " font:8pt tahoma, verdana;'><b>"
                + ((MyJSL_Item)_items.get_Item(get_SelectedIndex())).get_Message()
                + "</b></span>");
        }
    } //Render
} //MyJSL_CustomParse

上記で定義したカスタム コントロールを使用する例を次に示します。特に、この例では、実行時に表示するメッセージを決定する SelectedIndex 値と Message 値が代入されています。Register ディレクティブに示される値には、前のコマンド ラインが反映されます。

Visual Basic

<%@ Register TagPrefix="custom" Assembly="myControlBuilderAtt"
 Namespace="CustomControls" %>
 <h4>Using ControlBuilderAttribute Class<h4>
 <form runat="server">
  <custom:MyVB_CustomParse SelectedIndex="3" runat=server>
  <customitem Message="Visual Basic version. Item One selected"/>
  <customitem Message="Visual Basic version. Item Two selected"/>
  <customitem Message="Visual Basic version. Item Three selected"/>
  <customitem Message="Visual Basic version. Item Four selected"/>
  </custom:MyVB_CustomParse>
 </form>

C#

<%@ Register TagPrefix="custom" Assembly="myControlBuilderAtt"
 Namespace="CustomControls" %>
 <h4>Using ControlBuilderAttribute Class<h4>
 <form runat="server">
  <custom:MyCS_CustomParse SelectedIndex="2" runat=server>
  <customitem Message="C# version. Item One selected"/>
  <customitem Message="C# version. Item Two selected"/>
  <customitem Message="C# version. Item Three selected"/>
  <customitem Message="C# version. Item Four selected"/>
  </custom:MyCS_CustomParse>
 </form>

継承階層

System.Object
   System.Attribute
    System.Web.UI.ControlBuilderAttribute

スレッド セーフ

この型の public static (Visual Basic では Shared) メンバはすべて、スレッド セーフです。インスタンス メンバの場合は、スレッド セーフであるとは限りません。

プラットフォーム

Windows 98, Windows 2000 SP4, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

開発プラットフォームの中には、.NET Framework によってサポートされていないバージョンがあります。サポートされているバージョンについては、「システム要件」を参照してください。

バージョン情報

.NET Framework
サポート対象 : 2.0、1.1、1.0

参照

関連項目
ControlBuilderAttribute メンバ
System.Web.UI 名前空間
Attribute
その他の技術情報
ASP.NET コントロール デザイナの概要