ImportCatalogPart.GetWebPart(WebPartDescription) Método

Definición

Espacio de nombres:

System.Web.UI.WebControls.WebParts

Ensamblado:

System.Web.dll

Devuelve una referencia a un control WebPart basándose en los valores de la descripción pasada al método.

public:
 override System::Web::UI::WebControls::WebParts::WebPart ^ GetWebPart(System::Web::UI::WebControls::WebParts::WebPartDescription ^ description);

public override System.Web.UI.WebControls.WebParts.WebPart GetWebPart (System.Web.UI.WebControls.WebParts.WebPartDescription description);

override this.GetWebPart : System.Web.UI.WebControls.WebParts.WebPartDescription -> System.Web.UI.WebControls.WebParts.WebPart

Public Overrides Function GetWebPart (description As WebPartDescription) As WebPart

Parámetros

description

WebPartDescription

WebPartDescription que contiene detalles sobre el control.

Devoluciones

WebPart

Un control WebPart cuya descripción coincide con los valores contenidos en description.

Excepciones

ArgumentNullException

description es null.

ArgumentException

description no es un valor disponible de WebPartDescription.

Ejemplos

En el ejemplo de código siguiente se muestra cómo usar el GetWebPart método en una página web. El ejemplo tiene cuatro partes:

• Control de usuario que permite cambiar los modos de visualización en una página de elementos web.

• Página web que contiene un CatalogZone control y un ImportCatalogPart control, junto con código que usa el GetWebPart método .

• Un archivo de código fuente que contiene dos controles personalizados WebPart .

• Explicación de cómo funciona el ejemplo al cargar la página en un explorador.

La primera parte de este ejemplo de código es el control de usuario que permite a los usuarios cambiar los modos de presentación en una página web. Debe colocar el código fuente siguiente en un archivo y asignarle el nombre Displaymodemenucs.ascx o Displaymodemenuvb.ascx (dependiendo del idioma que use). Para obtener más información sobre los modos de presentación y una descripción del código fuente de este control, vea Walkthrough: Changing Display Modes on a Web Parts Page.

<%@ control language="C#" classname="DisplayModeMenuCS"%>
<script runat="server">
  
 // Use a field to reference the current WebPartManager.
  WebPartManager _manager;

  void Page_Init(object sender, EventArgs e)
  {
    Page.InitComplete += new EventHandler(InitComplete);
    
  }  

  void InitComplete(object sender, System.EventArgs e)
  {
    _manager = WebPartManager.GetCurrentWebPartManager(Page);

    String browseModeName = WebPartManager.BrowseDisplayMode.Name;

    // Fill the dropdown with the names of supported display modes.
    foreach (WebPartDisplayMode mode in _manager.SupportedDisplayModes)
    {
      String modeName = mode.Name;
      // Make sure a mode is enabled before adding it.
      if (mode.IsEnabled(_manager))
      {
        ListItem item = new ListItem(modeName, modeName);
        DisplayModeDropdown.Items.Add(item);
      }
    }

    // If shared scope is allowed for this user, display the scope-switching
    // UI and select the appropriate radio button for the current user scope.
    if (_manager.Personalization.CanEnterSharedScope)
    {
      Panel2.Visible = true;
      if (_manager.Personalization.Scope == PersonalizationScope.User)
        RadioButton1.Checked = true;
      else
        RadioButton2.Checked = true;
    }
    
  }
 
  // Change the page to the selected display mode.
  void DisplayModeDropdown_SelectedIndexChanged(object sender, EventArgs e)
  {
    String selectedMode = DisplayModeDropdown.SelectedValue;

    WebPartDisplayMode mode = _manager.SupportedDisplayModes[selectedMode];
    if (mode != null)
      _manager.DisplayMode = mode;
  }

  // Set the selected item equal to the current display mode.
  void Page_PreRender(object sender, EventArgs e)
  {
    ListItemCollection items = DisplayModeDropdown.Items;
    int selectedIndex = 
      items.IndexOf(items.FindByText(_manager.DisplayMode.Name));
    DisplayModeDropdown.SelectedIndex = selectedIndex;
  }

  // Reset all of a user's personalization data for the page.
  protected void LinkButton1_Click(object sender, EventArgs e)
  {
    _manager.Personalization.ResetPersonalizationState();
  }

  // If not in User personalization scope, toggle into it.
  protected void RadioButton1_CheckedChanged(object sender, EventArgs e)
  {
    if (_manager.Personalization.Scope == PersonalizationScope.Shared)
      _manager.Personalization.ToggleScope();
  }

  // If not in Shared scope, and if user is allowed, toggle the scope.
  protected void RadioButton2_CheckedChanged(object sender, EventArgs e)
  {
    if (_manager.Personalization.CanEnterSharedScope && 
        _manager.Personalization.Scope == PersonalizationScope.User)
      _manager.Personalization.ToggleScope();
  }
</script>
<div>
  <asp:Panel ID="Panel1" runat="server" 
    Borderwidth="1" 
    Width="230" 
    BackColor="lightgray"
    Font-Names="Verdana, Arial, Sans Serif" >
    <asp:Label ID="Label1" runat="server" 
      Text="&nbsp;Display Mode" 
      Font-Bold="true"
      Font-Size="8"
      Width="120" 
      AssociatedControlID="DisplayModeDropdown"/>
    <asp:DropDownList ID="DisplayModeDropdown" runat="server"  
      AutoPostBack="true" 
      Width="120"
      OnSelectedIndexChanged="DisplayModeDropdown_SelectedIndexChanged" />
    <asp:LinkButton ID="LinkButton1" runat="server"
      Text="Reset User State" 
      ToolTip="Reset the current user's personalization data for the page."
      Font-Size="8" 
      OnClick="LinkButton1_Click" />
    <asp:Panel ID="Panel2" runat="server" 
      GroupingText="Personalization Scope"
      Font-Bold="true"
      Font-Size="8" 
      Visible="false" >
      <asp:RadioButton ID="RadioButton1" runat="server" 
        Text="User" 
        AutoPostBack="true"
        GroupName="Scope" OnCheckedChanged="RadioButton1_CheckedChanged" />
      <asp:RadioButton ID="RadioButton2" runat="server" 
        Text="Shared" 
        AutoPostBack="true"
        GroupName="Scope" 
        OnCheckedChanged="RadioButton2_CheckedChanged" />
    </asp:Panel>
  </asp:Panel>
</div>

<%@ control language="vb" classname="DisplayModeMenuVB"%>
<script runat="server">
  ' Use a field to reference the current WebPartManager.
  Dim _manager As WebPartManager

  Sub Page_Init(ByVal sender As Object, ByVal e As EventArgs)
    AddHandler Page.InitComplete, AddressOf InitComplete
  End Sub

  Sub InitComplete(ByVal sender As Object, ByVal e As System.EventArgs)
    _manager = WebPartManager.GetCurrentWebPartManager(Page)
      
    Dim browseModeName As String = WebPartManager.BrowseDisplayMode.Name
      
    ' Fill the dropdown with the names of supported display modes.
    Dim mode As WebPartDisplayMode
    For Each mode In _manager.SupportedDisplayModes
      Dim modeName As String = mode.Name
      ' Make sure a mode is enabled before adding it.
      If mode.IsEnabled(_manager) Then
        Dim item As New ListItem(modeName, modeName)
        DisplayModeDropdown.Items.Add(item)
      End If
    Next mode
      
    ' If shared scope is allowed for this user, display the scope-switching
    ' UI and select the appropriate radio button for the current user scope.
    If _manager.Personalization.CanEnterSharedScope Then
      Panel2.Visible = True
      If _manager.Personalization.Scope = PersonalizationScope.User Then
        RadioButton1.Checked = True
      Else
        RadioButton2.Checked = True
      End If
    End If
   
  End Sub

  ' Change the page to the selected display mode.
  Sub DisplayModeDropdown_SelectedIndexChanged(ByVal sender As Object, _
    ByVal e As EventArgs)
    
    Dim selectedMode As String = DisplayModeDropdown.SelectedValue   
    Dim mode As WebPartDisplayMode = _
      _manager.SupportedDisplayModes(selectedMode)
    If Not (mode Is Nothing) Then
      _manager.DisplayMode = mode
    End If

  End Sub
   
  ' Set the selected item equal to the current display mode.
  Sub Page_PreRender(ByVal sender As Object, ByVal e As EventArgs)
    Dim items As ListItemCollection = DisplayModeDropdown.Items
    Dim selectedIndex As Integer = _
      items.IndexOf(items.FindByText(_manager.DisplayMode.Name))
    DisplayModeDropdown.SelectedIndex = selectedIndex

  End Sub

  ' Reset all of a user's personalization data for the page.
  Protected Sub LinkButton1_Click(ByVal sender As Object, _
    ByVal e As EventArgs)
    
    _manager.Personalization.ResetPersonalizationState()
    
  End Sub

  ' If not in User personalization scope, toggle into it.
  Protected Sub RadioButton1_CheckedChanged(ByVal sender As Object, _
    ByVal e As EventArgs)
    
    If _manager.Personalization.Scope = PersonalizationScope.Shared Then
      _manager.Personalization.ToggleScope()
    End If

  End Sub
   
  ' If not in Shared scope, and if user is allowed, toggle the scope.
  Protected Sub RadioButton2_CheckedChanged(ByVal sender As Object, _
    ByVal e As EventArgs)
    
    If _manager.Personalization.CanEnterSharedScope AndAlso _
      _manager.Personalization.Scope = PersonalizationScope.User Then
      _manager.Personalization.ToggleScope()
    End If

  End Sub

</script>
<div>
  <asp:Panel ID="Panel1" runat="server" 
    Borderwidth="1" 
    Width="230" 
    BackColor="lightgray"
    Font-Names="Verdana, Arial, Sans Serif" >
    <asp:Label ID="Label1" runat="server" 
      Text="&nbsp;Display Mode" 
      Font-Bold="true"
      Font-Size="8"
      Width="120" 
      AssociatedControlID="DisplayModeDropdown"/>
    <asp:DropDownList ID="DisplayModeDropdown" runat="server"  
      AutoPostBack="true" 
      Width="120"
      OnSelectedIndexChanged="DisplayModeDropdown_SelectedIndexChanged" />
    <asp:LinkButton ID="LinkButton1" runat="server"
      Text="Reset User State" 
      ToolTip="Reset the current user's personalization data for the page."
      Font-Size="8" 
      OnClick="LinkButton1_Click" />
    <asp:Panel ID="Panel2" runat="server" 
      GroupingText="Personalization Scope"
      Font-Bold="true"
      Font-Size="8" 
      Visible="false" >
      <asp:RadioButton ID="RadioButton1" runat="server" 
        Text="User" 
        AutoPostBack="true"
        GroupName="Scope" OnCheckedChanged="RadioButton1_CheckedChanged" />
      <asp:RadioButton ID="RadioButton2" runat="server" 
        Text="Shared" 
        AutoPostBack="true"
        GroupName="Scope" 
        OnCheckedChanged="RadioButton2_CheckedChanged" />
    </asp:Panel>
  </asp:Panel>
</div>

La segunda parte del ejemplo de código es la página web. En la parte superior de la página hay dos register directivas, una para el control de usuario y otra para el componente compilado que contiene los dos controles personalizados WebPart . Se hace referencia a ambos controles mediante declaración en el marcado de la página. En las referencias declarativas a los WebPart controles (ambos comienzan por un aspSample prefijo), tenga en cuenta que cada una tiene un exportMode="all" atributo agregado a él. Este atributo le permite exportar un . Archivo de descripción del elemento web para el control, que usará en un paso posterior para importar el control a una página.

Nota

Para permitir que los usuarios de una aplicación de elementos web exportan un archivo de descripción para WebPart los controles, también debe habilitar la característica de exportación en la aplicación web agregando un enableExport="true" atributo al <webParts> elemento (que es un elemento secundario del <system.web> elemento) en el archivo Web.config. La exportación está deshabilitada de forma predeterminada, por lo que si aún no ha habilitado la exportación de la aplicación, edite el archivo Web.config y hágalo ahora.

La página web también tiene una referencia declarativa al ImportCatalogPart control, anidada dentro de la jerarquía adecuada de elementos declarativos. Se GetWebPart llama al método dentro del código para el Button2_Click método .

<%@ page language="c#" %>
<%@ register TagPrefix="uc1" 
  TagName="DisplayModeMenuCS" 
  Src="DisplayModeMenuCS.ascx" %>
<%@ register tagprefix="aspSample" 
  Namespace="Samples.AspNet.CS.Controls" %>
  
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" 
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">

  // <snippet3>
  protected void Button1_Click(object sender, EventArgs e)
  {
    WebPartDescriptionCollection descriptions =
      ImportCatalogPart1.GetAvailableWebPartDescriptions();
    StringBuilder descriptionContent = new StringBuilder();
    foreach (WebPartDescription description in descriptions)
    {
      descriptionContent.AppendLine("<div><br /><strong>" + description.Title +
        "</strong><br />");
      descriptionContent.AppendLine("&nbsp;ID: " + description.ID + "<br />");
      descriptionContent.AppendLine("&nbsp;Description: " +
        description.Description + "<br /></div><hr />");
    }

    Label1.Text = "<h3>Catalog Contents</h3>" + descriptionContent.ToString();     

  }
  // </snippet3>

  // <snippet4>
  protected void Button2_Click(object sender, EventArgs e)
  {
    WebPartDescriptionCollection descriptions =
      ImportCatalogPart1.GetAvailableWebPartDescriptions();

    if (descriptions.Count > 0)
    {
      WebPart partToAdd =
        ImportCatalogPart1.GetWebPart(descriptions[0]);
      WebPartManager1.AddWebPart(partToAdd, zone1, 0);
    }
  }
  // </snippet4>
  
  protected void Page_Load(object sender, EventArgs e)
  {
    Button1.Visible = false;
    Button2.Visible = false;
    Label1.Visible = false;
  }

  protected void ImportCatalogPart1_PreRender(object sender, 
    EventArgs e)
  {
    Button1.Visible = true;
    Button2.Visible = true;
    Label1.Visible = true;
  }


</script>


<html xmlns="http://www.w3.org/1999/xhtml" >
  <head id="Head1" runat="server">
    <title>
      ImportCatalogPart Control
    </title>
  </head>
  <body>
    <form id="form1" runat="server">
      <asp:webpartmanager id="WebPartManager1" runat="server"  />
      <uc1:DisplayModeMenuCS ID="DisplayModeMenu1" runat="server" />
      <asp:webpartzone id="zone1" runat="server" >
        <PartTitleStyle BorderWidth="1"
          Font-Names="Verdana, Arial"
          Font-Size="110%"
          BackColor="LightBlue" />
        <zonetemplate>
          <asp:Calendar ID="Calendar1" runat="server" Title="My Calendar" />
          <aspsample:textdisplaywebpart id="wp1" runat="server" 
            Title="Text Display WebPart" exportmode="all" 
            description="Dynamically displays text in a label"/>
          <aspsample:userinfowebpart id="wp2" runat="server" 
            Title="User Info WebPart" exportmode="all" 
            description="Gathers user information" />
        </zonetemplate>
      </asp:webpartzone> 
      <asp:CatalogZone ID="CatalogZone1" runat="server">
        <ZoneTemplate>
          <asp:ImportCatalogPart ID="ImportCatalogPart1" 
            runat="server" 
            OnPreRender="ImportCatalogPart1_PreRender" />
        </ZoneTemplate>
      </asp:CatalogZone>
      <hr />
      <asp:Button ID="Button1" runat="server" 
        Text="Get WebPart Description" 
        OnClick="Button1_Click" />
      <br />
      <asp:Button ID="Button2" runat="server" 
        Text="Use GetWebPart" 
        OnClick="Button2_Click" />
      <asp:Label ID="Label1" runat="server" Text=""></asp:Label>  
    </form>
  </body>
</html>

<%@ page language="vb" %>
<%@ register TagPrefix="uc1" 
  TagName="DisplayModeMenuVB" 
  Src="DisplayModeMenuVB.ascx" %>
<%@ register tagprefix="aspSample" 
  Namespace="Samples.AspNet.VB.Controls" %>
  
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" 
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">

' <snippet3>
Protected Sub Button1_Click(ByVal sender As Object, ByVal e As EventArgs)
    Dim descriptions As WebPartDescriptionCollection = _
      ImportCatalogPart1.GetAvailableWebPartDescriptions()
    Dim descriptionContent As StringBuilder = New StringBuilder()
    Dim description As WebPartDescription
    For Each description In descriptions
      descriptionContent.AppendLine("<div><br /><strong>" + _
        description.Title + "</strong><br />")
      descriptionContent.AppendLine("&nbsp;ID: " + _
        description.ID + "<br />")
      descriptionContent.AppendLine("&nbsp;Description: " + _
        description.Description + "<br /></div><hr />")
    Next description

    Label1.Text = "<h3>Catalog Contents</h3>" + descriptionContent.ToString()
End Sub
' </snippet3>

' <snippet4>
Protected Sub Button2_Click(ByVal sender As Object, ByVal e As EventArgs)
    Dim descriptions As WebPartDescriptionCollection = _
      ImportCatalogPart1.GetAvailableWebPartDescriptions
    If (descriptions.Count > 0) Then
        Dim partToAdd As WebPart = ImportCatalogPart1.GetWebPart(descriptions(0))
        WebPartManager1.AddWebPart(partToAdd, zone1, 0)
    End If
End Sub
' </snippet4>

Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
    Button1.Visible = false
    Button2.Visible = false
    Label1.Visible = false
End Sub

Protected Sub ImportCatalogPart1_PreRender(ByVal sender As Object, ByVal e As EventArgs)
    Button1.Visible = true
    Button2.Visible = true
    Label1.Visible = true
End Sub

</script>


<html xmlns="http://www.w3.org/1999/xhtml" >
  <head id="Head1" runat="server">
    <title>
      ImportCatalogPart Control
    </title>
  </head>
  <body>
    <form id="form1" runat="server">
      <asp:webpartmanager id="WebPartManager1" runat="server"  />
      <uc1:DisplayModeMenuVB ID="DisplayModeMenu1" runat="server" />
      <asp:webpartzone id="zone1" runat="server" >
        <PartTitleStyle BorderWidth="1"
          Font-Names="Verdana, Arial"
          Font-Size="110%"
          BackColor="LightBlue" />
        <zonetemplate>
          <asp:Calendar ID="Calendar1" runat="server" Title="My Calendar" />
          <aspsample:textdisplaywebpart id="wp1" runat="server" 
            Title="Text Display WebPart" exportmode="all" 
            description="Dynamically displays text in a label"/>
          <aspsample:userinfowebpart id="wp2" runat="server" 
            Title="User Info WebPart" exportmode="all" 
            description="Gathers user information" />
        </zonetemplate>
      </asp:webpartzone> 
      <asp:CatalogZone ID="CatalogZone1" runat="server">
        <ZoneTemplate>
          <asp:ImportCatalogPart ID="ImportCatalogPart1" 
            runat="server" 
            OnPreRender="ImportCatalogPart1_PreRender" />
        </ZoneTemplate>
      </asp:CatalogZone>
      <hr />
      <asp:Button ID="Button1" runat="server" 
        Text="Get WebPart Description" 
        OnClick="Button1_Click" />
      <br />
      <asp:Button ID="Button2" runat="server" 
        Text="Use GetWebPart" 
        OnClick="Button2_Click" />
      <asp:Label ID="Label1" runat="server" Text=""></asp:Label>  
    </form>
  </body>
</html>

La tercera parte del ejemplo de código es el código fuente de los dos WebPart controles. Para que se ejecute el ejemplo de código, debe compilar este código fuente. Puede compilarlo explícitamente y colocar el ensamblado resultante en la carpeta Bin del sitio web o en la caché global de ensamblados. Como alternativa, puede colocar el código fuente en la carpeta App_Code del sitio, donde se compilará dinámicamente en tiempo de ejecución. En este ejemplo de código se usa la compilación dinámica. Para ver un tutorial que muestra ambos métodos de compilación, vea Walkthrough: Developing and Using a Custom Web Server Control.

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

namespace Samples.AspNet.CS.Controls
{
  [AspNetHostingPermission(SecurityAction.Demand,
    Level = AspNetHostingPermissionLevel.Minimal)]
  [AspNetHostingPermission(SecurityAction.InheritanceDemand,
    Level = AspNetHostingPermissionLevel.Minimal)]
  public class UserInfoWebPart : WebPart
  {
    HttpServerUtility server = HttpContext.Current.Server;
    private String _userNickName = "Add a nickname.";
    private String _userPetName = "Add a pet's name.";
    private DateTime _userSpecialDate = DateTime.Now;
    private Boolean _userIsCurrent = true;
    private JobTypeName _userJobType = JobTypeName.Unselected;
    public enum JobTypeName
    {
      Unselected = 0,
      Support = 1,
      Service = 2,
      Professional = 3, 
      Technical = 4,
      Manager = 5,
      Executive = 6
    }
    Label NickNameLabel;
    Label PetNameLabel;
    Label SpecialDateLabel;
    CheckBox IsCurrentCheckBox;
    Label JobTypeLabel;

    // Add the Personalizable and WebBrowsable attributes to the  
    // public properties, so that users can save property values  
    // and edit them with a PropertyGridEditorPart control.
    [Personalizable(), WebBrowsable, WebDisplayName("Nickname")]
    public String NickName
    {
      get 
      { 
        object o = ViewState["NickName"];
        if (o != null)
          return (string)o;
        else
          return _userNickName;        
      } 

      set { _userNickName = server.HtmlEncode(value); }
    }

    [Personalizable(), WebBrowsable, WebDisplayName("Pet Name")]
    public String PetName
    {
      get 
      { 
        object o = ViewState["PetName"];
        if (o != null)
          return (string)o;
        else
          return _userPetName;        
      }

      set { _userPetName = server.HtmlEncode(value); }
    }

    [Personalizable(), WebBrowsable(), WebDisplayName("Special Day")]
    public DateTime SpecialDay
    {
      get
      {
        object o = ViewState["SpecialDay"];
        if (o != null)
          return (DateTime)o;
        else
          return _userSpecialDate;
      }

      set { _userSpecialDate = value; }
    }

    [Personalizable(), WebBrowsable(), WebDisplayName("Job Type")]
    public JobTypeName UserJobType
    {
      get
      {
        object o = ViewState["UserJobType"];
        if (o != null)
          return (JobTypeName)o;
        else
          return _userJobType;
      }

      set { _userJobType = (JobTypeName)value; }
    }

    [Personalizable(), WebBrowsable(), WebDisplayName("Is Current")]
    public Boolean IsCurrent
    {
      get
      {
        object o = ViewState["IsCurrent"];
        if (o != null)
          return (Boolean)o;
        else
          return _userIsCurrent;
      }

      set { _userIsCurrent = value; }
    }

    protected override void CreateChildControls()
    {
      Controls.Clear();

      NickNameLabel = new Label();
      NickNameLabel.Text = this.NickName;
      SetControlAttributes(NickNameLabel);

      PetNameLabel = new Label();
      PetNameLabel.Text = this.PetName;
      SetControlAttributes(PetNameLabel);

      SpecialDateLabel = new Label();
      SpecialDateLabel.Text = this.SpecialDay.ToShortDateString();
      SetControlAttributes(SpecialDateLabel);

      IsCurrentCheckBox = new CheckBox();
      IsCurrentCheckBox.Checked = this.IsCurrent;
      SetControlAttributes(IsCurrentCheckBox);

      JobTypeLabel = new Label();
      JobTypeLabel.Text = this.UserJobType.ToString();
      SetControlAttributes(JobTypeLabel);

      ChildControlsCreated = true;
    }

    private void SetControlAttributes(WebControl ctl)
    {
      ctl.BackColor = Color.White;
      ctl.BorderWidth = 1;
      ctl.Width = 200;
      this.Controls.Add(ctl);
    }

    protected override void RenderContents(HtmlTextWriter writer)
    {
      writer.Write("Nickname:");
      writer.WriteBreak();
      NickNameLabel.RenderControl(writer);
      writer.WriteBreak();
      writer.Write("Pet Name:");
      writer.WriteBreak();
      PetNameLabel.RenderControl(writer);
      writer.WriteBreak();
      writer.Write("Special Date:");
      writer.WriteBreak();
      SpecialDateLabel.RenderControl(writer);
      writer.WriteBreak();
      writer.Write("Job Type:");
      writer.WriteBreak();
      JobTypeLabel.RenderControl(writer);
      writer.WriteBreak();
      writer.Write("Current:");
      writer.WriteBreak();
      IsCurrentCheckBox.RenderControl(writer);
    }
  }

  [AspNetHostingPermission(SecurityAction.Demand,
    Level = AspNetHostingPermissionLevel.Minimal)]
  [AspNetHostingPermission(SecurityAction.InheritanceDemand,
    Level = AspNetHostingPermissionLevel.Minimal)]
  public class TextDisplayWebPart : WebPart
  {
    private String _contentText = null;
    TextBox input;
    Label DisplayContent;
    Literal lineBreak;

    [Personalizable(), WebBrowsable]
    public String ContentText
    {
      get { return _contentText; }
      set { _contentText = value; }
    }

    protected override void CreateChildControls()
    {
      Controls.Clear();
      DisplayContent = new Label();
      DisplayContent.BackColor = Color.LightBlue;
      DisplayContent.Text = this.ContentText;
      this.Controls.Add(DisplayContent);

      lineBreak = new Literal();
      lineBreak.Text = @"<br />";
      Controls.Add(lineBreak);

      input = new TextBox();
      this.Controls.Add(input);
      Button update = new Button();
      update.Text = "Set Label Content";
      update.Click += new EventHandler(this.submit_Click);
      this.Controls.Add(update);
    }

    private void submit_Click(object sender, EventArgs e)
    {
      // Update the label string.
      if (!string.IsNullOrEmpty(input.Text))
      {
        _contentText = input.Text + @"<br />";
        input.Text = String.Empty;
        DisplayContent.Text = this.ContentText;
      }
    }
  }
}

Imports System.Collections
Imports System.ComponentModel
Imports System.Drawing
Imports System.Security.Permissions
Imports System.Web
Imports System.Web.UI
Imports System.Web.UI.WebControls
Imports System.Web.UI.WebControls.WebParts

Namespace Samples.AspNet.VB.Controls

  <AspNetHostingPermission(SecurityAction.Demand, _
    Level:=AspNetHostingPermissionLevel.Minimal)> _
  <AspNetHostingPermission(SecurityAction.InheritanceDemand, _
    Level:=AspNetHostingPermissionLevel.Minimal)> _
  Public Class UserInfoWebPart
    Inherits WebPart
    Private server As HttpServerUtility = HttpContext.Current.Server
    Private _userNickName As String = "Add a nickname."
    Private _userPetName As String = "Add a pet's name."
    Private _userSpecialDate As DateTime = DateTime.Now
    Private _userIsCurrent As [Boolean] = True
    Private _userJobType As JobTypeName = JobTypeName.Unselected

    Public Enum JobTypeName
      Unselected = 0
      Support = 1
      Service = 2
      Professional = 3
      Technical = 4
      Manager = 5
      Executive = 6
    End Enum

    Private NickNameLabel As Label
    Private PetNameLabel As Label
    Private SpecialDateLabel As Label
    Private IsCurrentCheckBox As CheckBox
    Private JobTypeLabel As Label

    ' Add the Personalizable and WebBrowsable attributes to the  
    ' public properties, so that users can save property values  
    ' and edit them with a PropertyGridEditorPart control.

    <Personalizable(), WebBrowsable(), WebDisplayName("Nickname")> _
    Public Property NickName() As String
      Get
        Dim o As Object = ViewState("NickName")
        If Not (o Is Nothing) Then
          Return CStr(o)
        Else
          Return _userNickName
        End If
      End Get
      Set(ByVal value As String)
        _userNickName = server.HtmlEncode(value)
      End Set
    End Property

    <Personalizable(), WebBrowsable(), WebDisplayName("Pet Name")> _
    Public Property PetName() As String
      Get
        Dim o As Object = ViewState("PetName")
        If Not (o Is Nothing) Then
          Return CStr(o)
        Else
          Return _userPetName
        End If
      End Get
      Set(ByVal value As String)
        _userPetName = server.HtmlEncode(value)
      End Set
    End Property

    <Personalizable(), WebBrowsable(), WebDisplayName("Special Day")> _
    Public Property SpecialDay() As DateTime
      Get
        Dim o As Object = ViewState("SpecialDay")
        If Not (o Is Nothing) Then
          Return CType(o, DateTime)
        Else
          Return _userSpecialDate
        End If
      End Get

      Set(ByVal value As DateTime)
        _userSpecialDate = value
      End Set
    End Property

    <Personalizable(), WebBrowsable(), WebDisplayName("Job Type")> _
    Public Property UserJobType() As JobTypeName
      Get
        Dim o As Object = ViewState("UserJobType")
        If Not (o Is Nothing) Then
          Return CType(o, JobTypeName)
        Else
          Return _userJobType
        End If
      End Get
      Set(ByVal value As JobTypeName)
        _userJobType = CType(value, JobTypeName)
      End Set
    End Property

    <Personalizable(), WebBrowsable(), WebDisplayName("Is Current")> _
    Public Property IsCurrent() As [Boolean]
      Get
        Dim o As Object = ViewState("IsCurrent")
        If Not (o Is Nothing) Then
          Return CType(o, [Boolean])
        Else
          Return _userIsCurrent
        End If
      End Get
      Set(ByVal value As [Boolean])
        _userIsCurrent = value
      End Set
    End Property

    Protected Overrides Sub CreateChildControls()
      Controls.Clear()

      NickNameLabel = New Label()
      NickNameLabel.Text = Me.NickName
      SetControlAttributes(NickNameLabel)

      PetNameLabel = New Label()
      PetNameLabel.Text = Me.PetName
      SetControlAttributes(PetNameLabel)

      SpecialDateLabel = New Label()
      SpecialDateLabel.Text = Me.SpecialDay.ToShortDateString()
      SetControlAttributes(SpecialDateLabel)

      IsCurrentCheckBox = New CheckBox()
      IsCurrentCheckBox.Checked = Me.IsCurrent
      SetControlAttributes(IsCurrentCheckBox)

      JobTypeLabel = New Label()
      JobTypeLabel.Text = Me.UserJobType.ToString()
      SetControlAttributes(JobTypeLabel)

      ChildControlsCreated = True

    End Sub

    Private Sub SetControlAttributes(ByVal ctl As WebControl)
      ctl.BackColor = Color.White
      ctl.BorderWidth = 1
      ctl.Width = 200
      Me.Controls.Add(ctl)
    End Sub

    Protected Overrides Sub RenderContents(ByVal writer As HtmlTextWriter)
      writer.Write("Nickname:")
      writer.WriteBreak()
      NickNameLabel.RenderControl(writer)
      writer.WriteBreak()
      writer.Write("Pet Name:")
      writer.WriteBreak()
      PetNameLabel.RenderControl(writer)
      writer.WriteBreak()
      writer.Write("Special Date:")
      writer.WriteBreak()
      SpecialDateLabel.RenderControl(writer)
      writer.WriteBreak()
      writer.Write("Job Type:")
      writer.WriteBreak()
      JobTypeLabel.RenderControl(writer)
      writer.WriteBreak()
      writer.Write("Current:")
      writer.WriteBreak()
      IsCurrentCheckBox.RenderControl(writer)

    End Sub

  End Class


  <AspNetHostingPermission(SecurityAction.Demand, _
    Level:=AspNetHostingPermissionLevel.Minimal)> _
  <AspNetHostingPermission(SecurityAction.InheritanceDemand, _
    Level:=AspNetHostingPermissionLevel.Minimal)> _
  Public Class TextDisplayWebPart
    Inherits WebPart
    Private _contentText As String = Nothing
    Private _fontStyle As String = Nothing
    Private input As TextBox
    Private DisplayContent As Label
    Private lineBreak As Literal

    <Personalizable(), WebBrowsable()> _
    Public Property ContentText() As String
      Get
        Return _contentText
      End Get
      Set(ByVal value As String)
        _contentText = value
      End Set
    End Property

    Protected Overrides Sub CreateChildControls()
      Controls.Clear()
      DisplayContent = New Label()
      DisplayContent.BackColor = Color.LightBlue
      DisplayContent.Text = Me.ContentText
      Me.Controls.Add(DisplayContent)

      lineBreak = New Literal()
      lineBreak.Text = "<br />"
      Controls.Add(lineBreak)

      input = New TextBox()
      Me.Controls.Add(input)
      Dim update As New Button()
      update.Text = "Set Label Content"
      AddHandler update.Click, AddressOf Me.submit_Click
      Me.Controls.Add(update)

    End Sub

    Private Sub submit_Click(ByVal sender As Object, _
                             ByVal e As EventArgs)
      ' Update the label string.
      If input.Text <> String.Empty Then
        _contentText = input.Text + "<br />"
        input.Text = String.Empty
        DisplayContent.Text = Me.ContentText
      End If

    End Sub

  End Class

End Namespace

Ahora ejecute el ejemplo de código. Cargue la página web en un explorador. El primer paso es exportar un . Archivo de descripción del elemento web para cada WebPart control (para y TextDisplayWebPart para el UserInfoWebPart control). Para cada control, haga clic en el menú verbos del control (representado por la flecha hacia abajo de la barra de título) y haga clic en Exportar. Siga las instrucciones para guardar un . Archivo de descripción del elemento web para el control. Después de exportar un archivo de descripción para cada control, cierre la página web y edite el origen de la página en un editor. Elimine y <aspSample:userinfowebpart> los elementos de declaración de <aspSample:textdisplaywebpart> control y, a continuación, guarde y cierre el archivo. (Está realizando este paso para simular un usuario que aún no tiene estos controles, por lo que puede importar los controles a la página).

Vuelva a cargar la página web en un explorador. Use el control de lista desplegable Modo de presentación y seleccione Catálogo para cambiar la página al modo de catálogo. En el ImportCatalogPart control , haga clic en el botón Examinar y vaya a . Archivos de elementos web que ha creado, seleccione uno y, a continuación, haga clic en el botón Cargar . Debe aparecer una referencia al control con una casilla junto a él. Ahora que la descripción del control se carga en el ImportCatalogPart control, haga clic en el botón Usar GetWebPart situado cerca de la parte inferior de la página. Esto demostrará el efecto de llamar al GetWebPart método y pasarle la descripción del control cargada actualmente en el ImportCatalogPart control. Tenga en cuenta que el control de servidor asociado se agrega inmediatamente a la página web, sin que el usuario tenga que hacer clic en el botón Agregar . El GetWebPart método , al que se llama en el Button2_Click método del origen de la página, devuelve el WebPart control asociado a la descripción actual que se carga en el ImportCatalogPart control . A continuación, se llama al AddWebPart método y el WebPart control se agrega directamente a la página. Esto muestra cómo agregar un control mediante programación desde el control sin intervención del ImportCatalogPart usuario.

Después de agregar el primer control, repita el proceso para agregar el segundo control a la página. Por último, haga clic en Cerrar para salir del modo de catálogo y devuelva la página al modo de exploración. Ambos controles personalizados deberían aparecer ahora en la página, que contienen los valores que tenían al exportar archivos de descripción anteriormente.

Comentarios

El GetWebPart método devuelve una referencia a un WebPart control cuyos detalles de descripción coinciden con los valores del WebPartDescription objeto pasado al método . Normalmente, este método se usa junto con el GetAvailableWebPartDescriptions método , que se usa para recuperar las descripciones de los controles del catálogo. Los controles individuales WebPart se pueden recuperar o manipular según sea necesario pasando objetos individuales WebPartDescription al GetWebPart método .

Consulte también

• GetAvailableWebPartDescriptions()
• controles de elementos web de ASP.NET