ControlBuilder クラス

[アーティクル]
03/28/2008

コントロールとその子コントロールを作成するときにページパーサーをサポートします。

この型のすべてのメンバの一覧については、ControlBuilder メンバを参照してください。

System.Object
System.Web.UI.ControlBuilder
派生クラス

Public Class ControlBuilder
[C#]
public class ControlBuilder
[C++]
public __gc class ControlBuilder
[JScript]
public class ControlBuilder

スレッドセーフ

この型の public static (Visual Basicでは Shared) のすべてのメンバは、マルチスレッド操作で安全に使用できます。インスタンスのメンバの場合は、スレッドセーフであるとは限りません。

解説

既定では、ページ上のすべてのコントロールが既定の ControlBuilder クラスに関連付けられます。このクラスは、カスタムコントロールタグ内にあるすべての入れ子のコントロールを格納する Controls コレクションに子コントロールを追加します。また、このクラスは、入れ子のコントロールタグの間にあるテキストのリテラルコントロールを作成します。独自のカスタムコントロールビルダクラスを定義して、この既定の動作をオーバーライドできます。既定の動作をオーバーライドするには、次のようにして、作成したコントロールビルダクラスに ControlBuilderAttribute を適用します。 [ControlBuilderAttribute(typeof(ControlBuilderType))]

使用例

[Visual Basic, C#, C++] テーブルの作成時に属性と内容が定義される Table コントロールを作成する例を次に示します。実行可能ファイルを作成するために使用するコマンドラインを次に示します。

vbc /r:System.dll /r:System.Web.dll /r:System.Drawing.dll /t:library /out:myWebAppPath/bin/vb_mycontrolbuilder.dll myControlBuilder.vb

csc /t:library /out:myWebAppPath/bin/cs_mycontrolbuilder.dll myControlBuilder.cs

 

'File name myControlBuilder.vb.
 
Imports System
Imports System.Web
Imports System.Web.UI
Imports System.Web.UI.WebControls
Imports System.Collections
Imports System.Drawing


Namespace CustomControls
    _
   
   Public Class MyCellVB
      Inherits Control
      Implements INamingContainer   
  ' Class Name: MyCellVB.
  ' Declares the class for the child controls to be included in the control collection.
  
      Private _id As String
      Private _value As String
      Private _backColor As Color
          
      Public Property CellID() As String
         Get
            Return _id
         End Get
         Set
            _id = value
         End Set
      End Property 
      
      Public Property Text() As String
         Get
            Return _value
         End Get
         Set
            _value = value
         End Set
      End Property 
      
      
      Public Property BackColor() As Color
         Get
            Return _backColor
         End Get
         Set
            _backColor = value
         End Set
      End Property
   End Class 'MyCellVB
    _ 
   Public Class MyControlBuilderVB
      Inherits ControlBuilder

      <System.Security.Permissions.PermissionSetAttribute(System.Security.Permissions.SecurityAction.Demand, Name:="FullTrust")> _
      Public Overrides Function GetChildControlType(tagName As String, attribs As IDictionary) As Type
         
         ' Allows TableRow without "runat=server" attribute to be added to the collection.
         If tagName.ToLower().EndsWith("mycellvb") Then
            Return GetType(MyCellVB)
         End If 
         Return Nothing
      End Function 'GetChildControlType
      
      ' Ignores literals between rows.
      <System.Security.Permissions.PermissionSetAttribute(System.Security.Permissions.SecurityAction.Demand, Name:="FullTrust")> _
      Public Overrides Sub AppendLiteralString(s As String)
      End Sub 'AppendLiteralString

   End Class 'MyControlBuilderVB
   
 <ControlBuilderAttribute(GetType(MyControlBuilderVB))>  _
 Public Class MyVB_CustomControl
      Inherits Control
      Implements INamingContainer 
      
  ' Class name: MyVB_CustomControl.
  ' Processes the element declarations within a control 
  ' declaration. This builds the actual control.
      
      ' Custom control to build programmatically.
      Private _table As Table
      
      Private _cellObjects As New Hashtable()
      
      ' Variables that must contain the control attributes as defined in the Web page.
      Private _rows As Integer
      Private _columns As Integer
      Private _title As String
      
      ' Rows property to be used as the attribute name in the Web page.     
      Public Property Rows () As String
         Get
            Return _rows
         End Get
         Set
            _rows = CInt(value)
         End Set
      End Property
      
     ' Columns property to be used as the attribute name in the Web page.
        
      Public Property Columns () As String
         Get
            Return _columns
         End Get
         Set
            _columns = CInt(value)
         End Set
      End Property
      
      ' Title property to be used as the attribute name in the Web page   
      Public Property Title() As String
         Get
            Return _title
         End Get
         Set
            _title = value
         End Set
      End Property
       
      
      Protected Sub createNewRow(rowNumber As Integer)
         
         ' Creates a row and adds it to the table.
         Dim row As TableRow
         
         row = New TableRow()
         _table.Rows.Add(row)
         
         ' Creates a cell that contains text.
         Dim y As Integer
         For y = 0 To Columns - 1
            appendCell(row, rowNumber, y)
         Next y 
      End Sub 'createNewRow
      
      
      Protected Sub appendCell(row As TableRow, rowNumber As Integer, cellNumber As Integer)
         Dim cell As TableCell
         Dim textbox As TextBox
         
         cell = New TableCell()
           
         textbox = New TextBox()
         
         cell.Controls.Add(textbox)
         
         textbox.ID = "r" + rowNumber.ToString() + "c" + cellNumber.ToString()
         
         ' Checks for the MyCellVB child object.
         
         If Not (_cellObjects(textbox.ID) Is Nothing) Then
            Dim cellLookup As MyCellVB
            cellLookup = CType(_cellObjects(textbox.ID), MyCellVB)
            
            textbox.Text = cellLookup.Text
            textbox.BackColor = cellLookup.BackColor
         
         Else
            textbox.Text = "Row: " + rowNumber.ToString() + " Cell: " + cellNumber.ToString()
         End If 
         
         row.Cells.Add(cell)
      End Sub 'appendCell
       
      ' Called at runtime when a child object is added to the collection.
      <System.Security.Permissions.PermissionSetAttribute(System.Security.Permissions.SecurityAction.Demand, Name:="FullTrust")> _  
      Protected Overrides Sub AddParsedSubObject(obj As Object)  
         
         If TypeOf obj Is MyCellVB Then
            
            Dim cell As MyCellVB
            
            cell = CType(obj, MyCellVB)
            Context.Trace.Write("CellObject", cell.CellID)
            
            _cellObjects.Add(cell.CellID, cell)
            Return
         End If
      End Sub 'AddParsedSubObject
      
      
      <System.Security.Permissions.PermissionSetAttribute(System.Security.Permissions.SecurityAction.Demand, Name:="FullTrust")> _
      Protected Overrides Sub OnPreRender(e As EventArgs)
      ' Sub name: OnPreRender.
      ' Carries out changes affecting the control state and renders the resulting UI.
  
         ' Increases the number of rows if needed.
         While _table.Rows.Count < Rows
            createNewRow(_table.Rows.Count)
         End While
         
         ' Checks that each row has the correct number of columns.
         Dim i As Integer
         For i = 0 To _table.Rows.Count - 1
            While _table.Rows(i).Cells.Count < Columns
               appendCell(_table.Rows(i), i, _table.Rows(i).Cells.Count)
            End While
            
            While _table.Rows(i).Cells.Count > Columns
               _table.Rows(i).Cells.RemoveAt((_table.Rows(i).Cells.Count - 1))
            End While
         Next i
      End Sub 'OnPreRender
       
      
      <System.Security.Permissions.PermissionSetAttribute(System.Security.Permissions.SecurityAction.Demand, Name:="FullTrust")> _
      Protected Overrides Sub CreateChildControls()
       ' Sub name: CreateChildControls.
       ' Adds the Table and the text controls to the control collection. 

         
         Dim [text] As LiteralControl
         
         ' Initializes the text control using the Title property.
         [text] = New LiteralControl("<h5>" + Title + "</h5>")
         Controls.Add([text])
         
         
         _table = New Table()
        
         Controls.Add(_table)
      End Sub 'CreateChildControls 
   End Class 'MyVB_CustomControl

End Namespace 'CustomControls


[C#] 

/* File name: myControlBuilder.cs. */

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

namespace CustomControls 
{
  public class MyTableCell : TableCell, INamingContainer {};
     
  public class MyCell  
  /*
   * Class name: MyCell.
   * Declares the class for the child controls to include in the control collection.
   */
  {
    string _id;
    string _value;
    Color _backColor;

    public string CellID 
    {
      get 
        {return _id;}
      set 
        {_id = value;}
    }

    public string Text 
    {
      get 
        {return _value;}
      set 
        {_value = value;}
    }

    public Color BackColor 
    {
      get 
        {return _backColor;}
      set 
        { _backColor = value;}
    }
  };

  public class MyControlBuilder   : ControlBuilder 
  {

    [System.Security.Permissions.PermissionSet(System.Security.Permissions.SecurityAction.Demand, Name="FullTrust")]
    public override Type GetChildControlType(string tagName, IDictionary attribs) 
    {
      // Allows TableRow without "runat=server" attribute to be added to the collection.
      if (tagName.ToLower().EndsWith("mycell"))
        return typeof(MyCell);
      return null;
    }

    [System.Security.Permissions.PermissionSet(System.Security.Permissions.SecurityAction.Demand, Name="FullTrust")]
    public override void AppendLiteralString(string s) 
    {
      // Ignores literals between rows.
    }

  }

  [ControlBuilderAttribute(typeof(MyControlBuilder))]
  public class MyCS_CustomControl: Control,  INamingContainer
  /*
   * Class name: MyCS_CustomControl.
   * Processes the element declarations within a control declaration. 
   * This builds the actual control.
  */
  {
    // Declares the custom control that must be built programmatically.
    Table _table;

    private String _title;
    private int _rows;
    private int _columns;

    Hashtable _cellObjects = new Hashtable();

   // Rows property to be used as the attribute name in the Web page.  
   public int Rows
   {
     get 
       {return _rows;}
     set 
       {_rows = value;}
   }

   // Columns property to be used as the attribute name in the Web page.
  public int Columns
  {
    get 
      {return _columns;}
    set 
      {_columns = value;}
  }
 
   // Title property to be used as the attribute name in the Web page.
   public string Title
   {
     get 
       {return _title;}
     set 
       {_title = value;}
   } 

   protected void createNewRow( int rowNumber ) 
   {

     // Creates a row and adds it to the table.
     TableRow row;

     row = new TableRow();
     _table.Rows.Add( row );

     // Creates a cell that contains text.

     for( int y=0; y < Columns ; y++ ) 
       appendCell( row, rowNumber, y );

    }

    protected void appendCell( TableRow row, int rowNumber, int cellNumber ) 
    {
      TableCell cell; 
      TextBox textbox;
      
      cell = new TableCell();    
      textbox = new TextBox();
      cell.Controls.Add( textbox );
      textbox.ID = "r" + rowNumber.ToString() + "c" + cellNumber.ToString();
          
      // Checks for the MyCell child object.
      if ( _cellObjects[textbox.ID] != null ) 
      {
        MyCell cellLookup;
        cellLookup = (MyCell) _cellObjects[textbox.ID];

        textbox.Text = cellLookup.Text;
        textbox.BackColor = cellLookup.BackColor;
      }
      else     
        textbox.Text = "Row: " + rowNumber.ToString()  + " Cell: " +   
        cellNumber.ToString();

        row.Cells.Add( cell );
           
   }

   // Called at runtime when a child object is added to the collection.  
   [System.Security.Permissions.PermissionSet(System.Security.Permissions.SecurityAction.Demand, Name="FullTrust")]
   protected override void AddParsedSubObject(object obj) 
   {
     MyCell cell = obj as MyCell;
     if (cell != null) 
     {
        _cellObjects.Add( cell.CellID, cell );
     }

   }

    [System.Security.Permissions.PermissionSet(System.Security.Permissions.SecurityAction.Demand, Name="FullTrust")]
    protected override void OnPreRender(EventArgs e)
    /*
     * Function name: OnPreRender.
     * Carries out changes affecting the control state and renders the resulting UI.
    */
    {

      // Increases the number of rows if needed.
      while (_table.Rows.Count < Rows)
      {
        createNewRow(_table.Rows.Count );
      }

      // Checks that each row has the correct number of columns.
      for (int i=0; i<_table.Rows.Count; i++)
      {
        while(_table.Rows[i].Cells.Count<Columns)
        {
          appendCell(_table.Rows[i], i, _table.Rows[i].Cells.Count);
        }

        while(_table.Rows[i].Cells.Count>Columns)
        {
          _table.Rows[i].Cells.RemoveAt(_table.Rows[i].Cells.Count - 1);
        }
       }
    }

    [System.Security.Permissions.PermissionSet(System.Security.Permissions.SecurityAction.Demand, Name="FullTrust")]
    protected override void CreateChildControls()
   /*
    * Function name: CreateChildControls.
    * Adds the Table and the text control to the control collection.
    */
    {
      LiteralControl text;

      // Initializes the text control using the Title property.
      text = new LiteralControl("<h5>" + Title + "</h5>");
      Controls.Add(text);

      _table = new Table();
      _table.BorderWidth = 2;
      Controls.Add(_table);
    }
  }
}


[C++] 

/* File name: myControlBuilder.cpp. */

#using <mscorlib.dll>
#using <System.Web.dll>
#using <System.dll>
#using <System.Drawing.dll>
using namespace System;
using namespace System::Web;
using namespace System::Web::UI;
using namespace System::Web::UI::WebControls;
using namespace System::Collections;
using namespace System::Drawing;

public __gc class MyTableCell : public TableCell, public INamingContainer
{
};

public __gc class MyCell
{
   /*
   * Class name: MyCell.
   * Declares the class for the child controls to include in the control collection.
   */
   String* _id;
   String* _value;
   Color _backColor;

public:
   __property String* get_CellID() 
   {
      return _id;
   }

   __property void set_CellID(String* value) 
   {
      _id = value;
   }

   __property String* get_Text() 
   {
      return _value;
   }

   __property void set_Text(String* value) 
   {
      _value = value;
   }

   __property Color get_BackColor() 
   {
      return _backColor;
   }

   __property void set_BackColor(Color value) 
   {
      _backColor = value;
   }
};

public __gc class MyControlBuilder : public ControlBuilder 
{
public:

   [System::Security::Permissions::PermissionSet(System::Security::Permissions::SecurityAction::Demand, Name="FullTrust")]
   Type * GetChildControlType(String* tagName, IDictionary* attribs) 
   {
      // Allows TableRow without "runat=server" attribute to be added to the collection.
      if (tagName->ToLower()->EndsWith(S"mycell"))
         return __typeof(MyCell);
      return 0;
   }

   [System::Security::Permissions::PermissionSet(System::Security::Permissions::SecurityAction::Demand, Name="FullTrust")]
   void AppendLiteralString(String* s) 
   {
      // Ignores literals between rows.
   }
};

[ControlBuilderAttribute(__typeof(MyControlBuilder))]
  public __gc class MyCS_CustomControl: public Control,  public INamingContainer
  {
     /*
     * Class name: MyCS_CustomControl.
     * Processes the element declarations within a control declaration.
     * This builds the actual control.
     */
     // Declares the custom control that must be built programmatically.
     Table* _table;

  private:
     String*  _title;
     int  _rows;
     int  _columns;

     Hashtable* _cellObjects;

     // Rows property to be used as the attribute name in the Web page.
  public:

     MyCS_CustomControl()
     {
        _cellObjects = new Hashtable();
     }

     __property int get_Rows() 
     {
        return _rows;
     }

     __property void set_Rows(int value) 
     {
        _rows = value;
     }

     // Columns property to be used as the attribute name in the Web page.
     __property int get_Columns() 
     {
        return _columns;
     }

     __property void set_Columns(int value) 
     {
        _columns = value;
     }

     // Title property to be used as the attribute name in the Web page.
     __property String* get_Title() 
     {
        return _title;
     }

     __property void set_Title(String* value) 
     {
        _title = value;
     }

  protected:
     void createNewRow(int rowNumber) 
     {
        // Creates a row and adds it to the table.
        TableRow * row;
        row = new TableRow();
        _table->Rows->Add(row);

        // Creates a cell that contains text.
        for (int y = 0; y < Columns ; y++)
           appendCell(row, rowNumber, y);
     }

     void appendCell(TableRow* row, int rowNumber, int cellNumber) 
     {
        TableCell * cell;
        TextBox * textbox;
        cell = new TableCell();
        textbox = new TextBox();
        cell->Controls->Add(textbox);
        textbox->ID = String::Concat(S"r", __box(rowNumber), S"c", __box(cellNumber));

        // Checks for the MyCell child object.
        if (_cellObjects->Item[textbox->ID] != 0) 
        {
           MyCell * cellLookup;
           cellLookup = dynamic_cast<MyCell*>(_cellObjects->Item[textbox->ID]);

           textbox->Text = cellLookup->Text;
           textbox->BackColor = cellLookup->BackColor;
        } 
        else
           textbox->Text = String::Concat(S"Row: ", __box(rowNumber), S"Cell: ", __box(cellNumber));

        row->Cells->Add(cell);
     }

     // Called at runtime when a child object is added to the collection.
     [System::Security::Permissions::PermissionSet(System::Security::Permissions::SecurityAction::Demand, Name="FullTrust")]
     void AddParsedSubObject(Object* obj) 
     {
        MyCell * cell = dynamic_cast<MyCell*>(obj);
        if (cell != 0)
           _cellObjects->Add(cell->CellID, cell);
     }

     [System::Security::Permissions::PermissionSet(System::Security::Permissions::SecurityAction::Demand, Name="FullTrust")]
     void OnPreRender(EventArgs* e)
     {
        /*
        * Function name: OnPreRender.
        * Carries out changes affecting the control state and renders the resulting UI.
        */

        // Increases the number of rows if needed.
        while (_table->Rows->Count < Rows)
           createNewRow(_table->Rows->Count);

        // Checks that each row has the correct number of columns.
        for (int i=0; i<_table->Rows->Count; i++) 
           while(_table->Rows->Item[i]->Cells->Count<Columns)
              appendCell(_table->Rows->Item[i], i, _table->Rows->Item[i]->Cells->Count);

        while(_table->Rows->Item[i]->Cells->Count>Columns)
           _table->Rows->Item[i]->Cells->RemoveAt(_table->Rows->Item[i]->Cells->Count - 1);
     }

     [System::Security::Permissions::PermissionSet(System::Security::Permissions::SecurityAction::Demand, Name="FullTrust")]
     void CreateChildControls()
     {
        /*
        * Function name: CreateChildControls.
        * Adds the Table and the text control to the control collection.
        */
        LiteralControl * text;

        // Initializes the text control using the Title property.
        text = new LiteralControl(String::Concat(S"<h5>",Title,S"</h5>"));
        Controls->Add(text);
        _table = new Table();
        _table->BorderWidth = 2;
        Controls->Add(_table);
     }
  };

[Visual Basic, C#, C++] 前述の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、実行時に属性と内容が定義されるテーブルを作成します。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。

 
<%@ Register TagPrefix="custom" Assembly="vb_mycontrolbuilder" Namespace="CustomControls" %>
<html>
<body>
 <h4>Using the ControlBuilder Class</h4>
 <form runat="server">
 <custom:MyVB_CustomControl Rows="2" Columns="2" Title="VB Custom Control Table" runat="server">
 <custom:MyCellVB CellID="r0c0" BackColor="magenta" Text="Hello"/>
 <custom:MyCellVB CellID="r0c1" BackColor="aqua" Text="Customer,"/>
 <custom:MyCellVB CellID="r1c0" BackColor="yellow" Text="How Are"/>
 <custom:MyCellVB CellID="r1c1" BackColor="red" Text="You?"/>
 </custom:MyVB_CustomControl>
 </form>
</body>
</html>
[C#] 
<%@ Register TagPrefix="custom" Assembly="cs_mycontrolbuilder" Namespace="CustomControls" %>
<html>
 <body>
 <h4>Using the ControlBuilder Class</h4>
 <form runat="server">
 <custom:MyCS_CustomControl ID="csTableId" rows="2" columns="2" Title="C# Custom Control Table" runat=server>
 <custom:MyCell CellID="r0c0" BackColor="red" Text="Hello"/>
 <custom:MyCell CellID="r0c1" BackColor="yellow" Text="Customer,"/>
 <custom:MyCell CellID="r1c0" BackColor="aqua" Text="How Are"/>
 <custom:MyCell CellID="r1c1" BackColor="magenta" Text="You?"/>
 </custom:MyCS_CustomControl>
 </form>
 </body>
</html>

[JScript] JScript のサンプルはありません。Visual Basic、C#、および C++ のサンプルを表示するには、このページの左上隅にある言語のフィルタボタンをクリックします。

必要条件

名前空間: System.Web.UI

プラットフォーム: Windows 2000, Windows XP Professional, Windows Server 2003 ファミリ

アセンブリ: System.Web (System.Web.dll 内)

参照

ControlBuilder メンバ | System.Web.UI 名前空間 | Control | Page | ControlBuilderAttribute

次の方法で共有

ControlBuilder クラス

スレッドセーフ

解説

使用例

必要条件

参照

その他のリソース