ControlBuilder Classe

Definição

Dá suporte ao analisador de página ao criar um controle e os controles filhos que ele contém.Supports the page parser in building a control and the child controls it contains.

public ref class ControlBuilder
public class ControlBuilder
type ControlBuilder = class
Public Class ControlBuilder
Herança
ControlBuilder
Derivado

Exemplos

O exemplo de código a seguir Table cria um controle cujos atributos e conteúdo são definidos no momento em que a tabela é criada.The following code example creates a Table control whose attributes and content are defined at the time the table is built. A seguir está a linha de comando a ser usada para criar o executável.The following is the command line to use to build the executable.

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

namespace CustomControls
{
    [AspNetHostingPermission(SecurityAction.Demand,
        Level = AspNetHostingPermissionLevel.Minimal)]
    public class MyTableCell : TableCell, INamingContainer { };

    [AspNetHostingPermission(SecurityAction.Demand,
        Level = AspNetHostingPermissionLevel.Minimal)]
    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; }
        }
    };

    [AspNetHostingPermission(SecurityAction.Demand,
    Level = AspNetHostingPermissionLevel.Minimal)]
    public class MyControlBuilder : ControlBuilder
    {

        public override Type GetChildControlType(string tagName, IDictionary attribs)
        {
            // Allows TableRow without "runat=server" attribute to be added to the collection.
            if (String.Compare(tagName, "mycell", true) == 0)
                return typeof(MyCell);
            return null;
        }

        public override void AppendLiteralString(string s)
        {
            // Ignores literals between rows.
        }

    }
    [AspNetHostingPermission(SecurityAction.Demand,
        Level = AspNetHostingPermissionLevel.Minimal)]
    [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.  
        protected override void AddParsedSubObject(object obj)
        {
            MyCell cell = obj as MyCell;
            if (cell != null)
            {
                _cellObjects.Add(cell.CellID, cell);
            }

        }

        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);
                }
            }
        }

        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);
        }
    }
}
Imports System.Web
Imports System.Web.UI
Imports System.Web.UI.WebControls
Imports System.Collections
Imports System.Drawing
Imports System.Security.Permissions


Namespace CustomControls

    <AspNetHostingPermission(SecurityAction.Demand, Level:=AspNetHostingPermissionLevel.Minimal)> _
    Public Class MyTableCell
        Inherits TableCell
        Implements INamingContainer
    End Class


    <AspNetHostingPermission(SecurityAction.Demand, Level:=AspNetHostingPermissionLevel.Minimal)> _
    Public Class MyCell
        Inherits Control
        Implements INamingContainer
        ' Class Name: MyCell.
        ' 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(ByVal value As String)
                _id = value
            End Set
        End Property

        Public Property Text() As String
            Get
                Return _value
            End Get
            Set(ByVal value As String)
                _value = value
            End Set
        End Property


        Public Property BackColor() As Color
            Get
                Return _backColor
            End Get
            Set(ByVal value As Color)
                _backColor = value
            End Set
        End Property
    End Class

    <AspNetHostingPermission(SecurityAction.Demand, Level:=AspNetHostingPermissionLevel.Minimal)> _
    Public Class MyControlBuilderVB
        Inherits ControlBuilder

        Public Overrides Function GetChildControlType(ByVal tagName As String, ByVal attribs As IDictionary) As Type

            ' Allows TableRow without "runat=server" attribute to be added to the collection.
            If (String.Compare(tagName, "mycell", True) = 0) Then
                Return GetType(MyCell)
            End If
            Return Nothing
        End Function

        ' Ignores literals between rows.
        Public Overrides Sub AppendLiteralString(ByVal s As String)
            ' Ignores literals between rows.
        End Sub

    End Class

    <AspNetHostingPermission(SecurityAction.Demand, Level:=AspNetHostingPermissionLevel.Minimal), 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 Integer
            Get
                Return _rows
            End Get
            Set(ByVal value As Integer)
                _rows = value
            End Set
        End Property

        ' Columns property to be used as the attribute name in the Web page.

        Public Property Columns() As Integer
            Get
                Return _columns
            End Get
            Set(ByVal value As Integer)
                _columns = 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(ByVal value As String)
                _title = value
            End Set
        End Property


        Protected Sub createNewRow(ByVal 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


        Protected Sub appendCell(ByVal row As TableRow, ByVal rowNumber As Integer, ByVal 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 MyCell child object.
            If Not (_cellObjects(textbox.ID) Is Nothing) Then
                Dim cellLookup As MyCell
                cellLookup = CType(_cellObjects(textbox.ID), MyCell)

                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

        ' Called at runtime when a child object is added to the collection.
        Protected Overrides Sub AddParsedSubObject(ByVal obj As Object)

            Dim cell As MyCell = CType(obj, MyCell)
            If Not (cell Is Nothing) Then
                _cellObjects.Add(cell.CellID, cell)
            End If
        End Sub


        Protected Overrides Sub OnPreRender(ByVal 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


        <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
    End Class

End Namespace

O exemplo de código a seguir usa o controle personalizado anterior.The following code example uses the previous custom control. Em particular, ele cria uma tabela cujos atributos e conteúdo são definidos em tempo de execução.In particular, it builds a table whose attributes and content are defined at run time. Observe que os valores mostrados na diretiva @ Register refletem a linha de comando anterior.Notice that the values shown in the @ Register directive reflect the previous command line.

<%@ Page Language="C#" %>
<%@ Register TagPrefix="AspNetSamples" Assembly="cs_mycontrolbuilder" Namespace="CustomControls" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>ControlBuilder Example</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
       <AspNetSamples:MyCS_CustomControl id="Custom1" 
                                         title="Auto-Generated Table"
                                         columns="3"
                                         rows="3"  
                                         runat="server">
         <mycell cellid="r0c0" BackColor="red" text="red cell"></mycell>
         <mycell cellid="r2c2" BackColor="green" text="green cell"></mycell>
       </AspNetSamples:MyCS_CustomControl>
    </div>
    </form>
</body>
</html>
<%@ Page Language="VB" %>
<%@ Register TagPrefix="AspNetSamples" Assembly="vb_mycontrolbuilder" Namespace="CustomControls" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>ControlBuilder Example</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
       <AspNetSamples:MyVB_CustomControl id="Custom1" 
                                         title="Auto-Generated Table"
                                         columns="3"
                                         rows="3"  
                                         runat="server">
         <mycell cellid="r0c0" BackColor="red" text="red cell"></mycell>
         <mycell cellid="r2c2" BackColor="green" text="green cell"></mycell>
       </AspNetSamples:MyVB_CustomControl>
    </div>
    </form>
</body>
</html>

Comentários

Por padrão, cada controle em uma página é associado a uma classe ControlBuilder padrão.By default, every control on a page is associated with a default ControlBuilder class. Durante a análise, a estrutura da página ASP.NET cria uma árvore ControlBuilder de objetos correspondente à árvore de controles da página.During parsing, the ASP.NET page framework builds a tree of ControlBuilder objects corresponding to the tree of controls for the page. Em ControlBuilder seguida, a árvore é usada para gerar o código da página para criar a árvore de controle.The ControlBuilder tree is then used to generate page code to create the control tree. Além dos controles filho, o ControlBuilder define o comportamento de como o conteúdo dentro de marcas de controle é analisado.In addition to child controls, the ControlBuilder defines the behavior of how the content within control tags is parsed. Você pode substituir esse comportamento padrão definindo sua própria classe personalizada do construtor de controle.You can override this default behavior by defining your own custom control builder class. Isso é feito aplicando um ControlBuilderAttribute atributo à sua classe do construtor de controle da seguinte maneira:This is done by applying a ControlBuilderAttribute attribute to your control builder class as follows:

[ControlBuilderAttribute(typeof(ControlBuilderType))]

Construtores

ControlBuilder()

Inicializa uma nova instância da classe ControlBuilder.Initializes a new instance of the ControlBuilder class.

Campos

DesignerFilter

Representa a cadeia de caracteres literal "__designer".Represents the "__designer" literal string.

Propriedades

BindingContainerBuilder

Obtém o construtor de controle que corresponde ao contêiner de associação para o controle que esse construtor cria.Gets the control builder that corresponds to the binding container for the control that this builder creates.

BindingContainerType

Obtém o tipo do contêiner de associação para o controle que esse construtor cria.Gets the type of the binding container for the control that this builder creates.

ComplexPropertyEntries

Obtém uma coleção de entradas de propriedade complexa.Gets a collection of complex property entries.

ControlType

Obtém o Type para o controle a ser criado.Gets the Type for the control to be created.

CurrentFilterResolutionService

Obtém um objeto IFilterResolutionService que é usado para gerenciar serviços relacionados ao filtro de dispositivo ao analisar e persistir controles no designer.Gets an IFilterResolutionService object that is used to manage device-filter related services when parsing and persisting controls in the designer.

DeclareType

Obtém o tipo que será usado pela geração de código para declarar o controle.Gets the type that will be used by code generation to declare the control.

FChildrenAsProperties

Obtém um valor que determina se o controle tem um ParseChildrenAttribute com ChildrenAsProperties definido como true.Gets a value that determines whether the control has a ParseChildrenAttribute with ChildrenAsProperties set to true.

FIsNonParserAccessor

Obtém um valor que determina se o controle implementa a interface IParserAccessor.Gets a value that determines whether the control implements the IParserAccessor interface.

HasAspCode

Obtém um valor que indica se o controle contém algum bloco de código.Gets a value indicating whether the control contains any code blocks.

ID

Obtém ou define a propriedade do identificador para o controle a ser criado.Gets or sets the identifier property for the control to be built.

InDesigner

Retorna se o ControlBuilder está sendo executado no designer.Returns whether the ControlBuilder is running in the designer.

InPageTheme

Obtém um valor booliano que indica se este objeto ControlBuilder é usado para gerar os temas de página.Gets a Boolean value indicating whether this ControlBuilder object is used to generate page themes.

ItemType

Obtém o tipo definido no contêiner de associação.Gets the type set on the binding container.

Localize

Obtém um valor booliano que indica se o controle criado por este objeto ControlBuilder está localizado.Gets a Boolean value indicating whether the control that is created by this ControlBuilder object is localized.

NamingContainerType

Obtém o tipo do contêiner de nomenclatura para o controle que esse construtor cria.Gets the type of the naming container for the control that this builder creates.

PageVirtualPath

Obtém o caminho virtual de uma página a ser criada por esta instância ControlBuilder.Gets the virtual path of a page to be built by this ControlBuilder instance.

Parser

Obtém o TemplateParser responsável por analisar o controle.Gets the TemplateParser responsible for parsing the control.

ServiceProvider

Obtém o objeto de serviço para esse objeto ControlBuilder.Gets the service object for this ControlBuilder object.

SubBuilders

Obtém uma lista de objetos ControlBuilder filho para esse objeto ControlBuilder.Gets a list of child ControlBuilder objects for this ControlBuilder object.

TagName

Obtém o nome da marca para o controle a ser criado.Gets the tag name for the control to be built.

TemplatePropertyEntries

Obtém uma coleção de entradas de propriedade de modelo.Gets a collection of template property entries.

ThemeResolutionService

Obtém um objeto IThemeResolutionService que é usado no tempo de design para gerenciar os temas e capas do controle.Gets an IThemeResolutionService object that is used in design time to manage control themes and skins.

Métodos

AllowWhitespaceLiterals()

Determina se literais de espaço em branco são permitidos no conteúdo entre marcas de abertura e fechamento do controle.Determines whether white space literals are permitted in the content between a control's opening and closing tags. Esse método é chamado pela estrutura de página ASP.NET.This method is called by the ASP.NET page framework.

AppendLiteralString(String)

Adiciona o conteúdo literal especificado a um controle.Adds the specified literal content to a control. Esse método é chamado pela estrutura de página ASP.NET.This method is called by the ASP.NET page framework.

AppendSubBuilder(ControlBuilder)

Adiciona construtores ao objeto ControlBuilder para quaisquer controles filho que pertençam ao controle de contêiner.Adds builders to the ControlBuilder object for any child controls that belong to the container control.

BuildObject()

Cria uma instância de tempo de design do controle que é referenciado por esse objeto ControlBuilder.Builds a design-time instance of the control that is referred to by this ControlBuilder object.

CloseControl()

Chamado pelo analisador para informar o construtor que a análise das marcas de abertura e fechamento do controle está concluída.Called by the parser to inform the builder that the parsing of the control's opening and closing tags is complete.

CreateBuilderFromType(TemplateParser, ControlBuilder, Type, String, String, IDictionary, Int32, String)

Cria um objeto ControlBuilder do tipo de objeto e do nome da marca especificados, bem como outros parâmetros que definem o construtor.Creates a ControlBuilder object from the specified tag name and object type, as well as other parameters defining the builder.

Equals(Object)

Determina se o objeto especificado é igual ao objeto atual.Determines whether the specified object is equal to the current object.

(Herdado de Object)
GetChildControlType(String, IDictionary)

Obtém o Type do tipo de controle correspondente a uma marca filha.Obtains the Type of the control type corresponding to a child tag. Esse método é chamado pela estrutura de página ASP.NET.This method is called by the ASP.NET page framework.

GetHashCode()

Serve como a função de hash padrão.Serves as the default hash function.

(Herdado de Object)
GetObjectPersistData()

Cria o objeto ObjectPersistData para este objeto ControlBuilder.Creates the ObjectPersistData object for this ControlBuilder object.

GetResourceKey()

Recupera a chave de recurso para este objeto ControlBuilder.Retrieves the resource key for this ControlBuilder object.

GetType()

Obtém o Type da instância atual.Gets the Type of the current instance.

(Herdado de Object)
HasBody()

Determina se um controle tem uma marca de abertura e de fechamento.Determines if a control has both an opening and closing tag. Esse método é chamado pela estrutura de página ASP.NET.This method is called by the ASP.NET page framework.

HtmlDecodeLiterals()

Determina se a cadeia de caracteres literal de um controle HTML deve ser decodificada para HTML.Determines whether the literal string of an HTML control must be HTML decoded. Esse método é chamado pela estrutura de página ASP.NET.This method is called by the ASP.NET page framework.

Init(TemplateParser, ControlBuilder, Type, String, String, IDictionary)

Inicializa o ControlBuilder para uso após ele ser instanciado.Initializes the ControlBuilder for use after it is instantiated. Esse método é chamado pela estrutura de página ASP.NET.This method is called by the ASP.NET page framework.

MemberwiseClone()

Cria uma cópia superficial do Object atual.Creates a shallow copy of the current Object.

(Herdado de Object)
NeedsTagInnerText()

Determina se o construtor de controle precisa obter seu texto interno.Determines if the control builder needs to get its inner text. Se sim, o método SetTagInnerText(String) deve ser chamado.If so, the SetTagInnerText(String) method must be called. Esse método é chamado pela estrutura de página ASP.NET.This method is called by the ASP.NET page framework.

OnAppendToParentBuilder(ControlBuilder)

Notifica o ControlBuilder que está sendo adicionado a um construtor de controle pai.Notifies the ControlBuilder that it is being added to a parent control builder.

ProcessGeneratedCode(CodeCompileUnit, CodeTypeDeclaration, CodeTypeDeclaration, CodeMemberMethod, CodeMemberMethod)

Permite que os criadores de controle personalizado acessem o CodeDom (Modelo de Objeto do Documento de Código) gerado e insiram e modifiquem o código durante o processo de análise e criação de controles.Enables custom control builders to access the generated Code Document Object Model (CodeDom) and insert and modify code during the process of parsing and building controls.

SetResourceKey(String)

Define a chave de recurso para este objeto ControlBuilder.Sets the resource key for this ControlBuilder object.

SetServiceProvider(IServiceProvider)

Define o objeto de serviço para esse objeto ControlBuilder.Sets the service object for this ControlBuilder object.

SetTagInnerText(String)

Fornece o ControlBuilder com o texto interno da marca do controle.Provides the ControlBuilder with the inner text of the control tag.

ToString()

Retorna uma cadeia de caracteres que representa o objeto atual.Returns a string that represents the current object.

(Herdado de Object)

Aplica-se a

Veja também