支持页分析器生成控件及其包含的子控件。

有关此类型所有成员的列表，请参阅 ControlBuilder 成员。

System.Object
   System.Web.UI.ControlBuilder
      派生类

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

线程安全

此类型的所有公共静态（Visual Basic 中为 Shared）成员是线程安全的。但不保证任何实例成员是线程安全的。

备注

默认情况下，页上的每个控件都与一个默认的 ControlBuilder 类关联。对于在自定义控件标记中遇到的每个嵌套控件，此类将一个子控件添加到 Controls 集合。此外，它为位于嵌套控件标记之间的文本创建文本控件。您可以通过定义自己的自定义控件生成器类来重写此默认行为。具体的方法是将 ControlBuilderAttribute 应用到您的控件生成器类，如下所示：[ControlBuilderAttribute(typeof(ControlBuilderType))]

示例

[Visual Basic, C#, C++] 下面的示例创建一个 Table 控件，它的属性和内容在生成此表时定义。以下是用于生成可执行文件的命令行。

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 

[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);
    }
  }
}
[Visual Basic, C#, C++] 下面的示例使用前面的自定义控件。具体说来，它生成一个属性和内容在运行时定义的表。注意 Register 指令中显示的值反映上一个命令行。
[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>

要求

命名空间: System.Web.UI

平台: Windows 2000, Windows XP Professional, Windows Server 2003 系列

程序集: System.Web (在 System.Web.dll 中)