ControlDesigner.Initialize(IComponent) Metode

Referensi

Definisi

Ruang nama:: System.Web.UI.Design

Rakitan:: System.Design.dll

Penting

Beberapa informasi terkait produk prarilis yang dapat diubah secara signifikan sebelum dirilis. Microsoft tidak memberikan jaminan, tersirat maupun tersurat, sehubungan dengan informasi yang diberikan di sini.

Menginisialisasi perancang kontrol dan memuat komponen yang ditentukan.

public:
 override void Initialize(System::ComponentModel::IComponent ^ component);

public override void Initialize (System.ComponentModel.IComponent component);

override this.Initialize : System.ComponentModel.IComponent -> unit

Public Overrides Sub Initialize (component As IComponent)

Parameter

component: IComponent

Kontrol sedang dirancang.

Contoh

Contoh kode berikut menunjukkan cara menggunakan kelas kontrol dan kelas perancang kontrol yang mengambil Initialize alih metode untuk menginisialisasi variabel internal.

using System;
using System.ComponentModel;
using System.Web.UI;
using System.Web.UI.Design;
using System.Web.UI.WebControls;

namespace AspNet.Samples
{
    // Create a custom class to render the Text property
    [Designer(typeof(SimpleDesigner)), DefaultProperty("Text"), 
    ToolboxData("<{0}:Simple runat=\"server\"></{0}:Simple>")]
    public sealed class Simple : WebControl
    {
        public Simple()
        { }

        // Create a Text property
        [Browsable(true), Bindable(true), 
            PersistenceMode(PersistenceMode.Attribute)]
        public string Text
        {
            get
            {
                object o = ViewState["TextProp"];
                return (o == null) ? "Sample Text" : (string)o;
            }
            set { ViewState["TextProp"] = value; }
        }

        // Render the text inside the control
        protected override void RenderContents(HtmlTextWriter writer)
        {
            writer.Write(Text);
        }
    }
}

namespace AspNet.Samples
{
    //Create a designer class for the Simple control
    public sealed class SimpleDesigner : ControlDesigner
    {
        // Declare a reference to the Simple class
        private Simple simpleControl;

        public SimpleDesigner()
        { }

        public override void Initialize(IComponent ponent)
        {
            base.Initialize(ponent);

            // Get a reference to the control
            simpleControl = (Simple)ponent;

            //Set Text to the control's ID
            simpleControl.Text = simpleControl.ID;
        }

        // Allow resizing the control in the design host
        public override bool AllowResize
        {
            get
            {
                return true;
            }
        }

        public override string GetDesignTimeHtml()
        {
            if (simpleControl.Text.Length > 0)
            {
                string spec = "<a href='{0}.aspx'>{0}</a>";
                return String.Format(spec, simpleControl.Text);
            }
            else
            {
                return GetEmptyDesignTimeHtml();
            }
        }
    }
}

' Create a designer class for a custom class,
' named Simple.
Imports System.ComponentModel
Imports System.IO
Imports System.Web
Imports System.Web.UI
Imports System.Web.UI.Design
Imports System.Web.UI.WebControls
Imports System.Security.Permissions
Imports AspNet.Samples

Namespace AspNet.Samples

   Public NotInheritable Class SimpleDesigner
      Inherits System.Web.UI.Design.ControlDesigner
      ' Declare a reference to the Simple class
      Private simpleControl As Simple
  
      ' Create a constructor for the designer class
      ' When an instance of the designer is created,
      ' the Text property of the instance of a Simple control
      ' is set to the designer's ID property.
      ' the designer is called.
      Public Sub New()
        simpleControl = CType(Component, Simple)      
        simpleControl.Text = Me.ID
      End Sub

      ' Override the Initialize method to ensure
      ' that the designer is always working with
      ' an instance of the Simple class.
      Overrides Public Sub Initialize( _
       ByVal component As IComponent _
      )
      
        If Not (component Is simpleControl)
                throw new ArgumentException( _
                 "The component must be an instance of the Simple class.", _
                 "component")
        End If

        MyBase.Initialize(component)
      
      End Sub
      
      Overrides Public ReadOnly Property AllowResize As Boolean
        Get
          Return True
        End Get
      End Property
      
      Public Overrides Function GetDesignTimeHtml() As String
         ' Component is the instance of the component or control that
         ' this designer object is associated with. This property is 
         ' inherited from System.ComponentModel.ComponentDesigner.
         simpleControl = CType(Component, Simple)
         
         If simpleControl.Text.Length > 0 Then
            Dim sw As New StringWriter()
            Dim tw As New HtmlTextWriter(sw)
            
            Dim placeholderLink As New HyperLink()
            
            ' Put simpleControl.Text into the link's Text.
            placeholderLink.Text = simpleControl.Text
            placeholderLink.NavigateUrl = simpleControl.Text
            placeholderLink.RenderControl(tw)
            
            Return sw.ToString()
         Else
            Return GetEmptyDesignTimeHtml()
         End If
      End Function

      ' Override the OnControlResize method to
      ' set the IsDirty property to true and
      ' call the UpdateDesignTimeHtml method.      
      Overrides Protected Sub OnControlResize()
        Me.IsDirty = True
        Me.UpdateDesignTimeHtml
      End Sub
      
   End Class
End Namespace

Keterangan

Metode Initialize ini dipanggil oleh host desain untuk menyelesaikan tindakan berikut:

Muat perancang kontrol dengan komponen yang akan didesain.
Siapkan tampilan pada kontrol menggunakan SetViewFlags metode .
Verifikasi bahwa kontrol terkait berjenis yang tepat.

Berlaku untuk

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