IPersonalizable.IsDirty Proprietà

  • Riferimento

Definizione

Spazio dei nomi:
System.Web.UI.WebControls.WebParts
Assembly:
System.Web.dll

Ottiene un valore che indica se i dati personalizzati gestiti da un controllo sono stati modificati.

public:
 property bool IsDirty { bool get(); };
public bool IsDirty { get; }
member this.IsDirty : bool
Public ReadOnly Property IsDirty As Boolean

Valore della proprietà

Boolean

true se i dati personalizzati gestiti con l'interfaccia IPersonalizable sono stati modificati; in caso contrario, false.

Esempio

Nell'esempio di codice seguente viene illustrato l'uso della IsDirty proprietà . La prima parte dell'esempio è la pagina Web che ospita un WebPart controllo .

<%@ Page Language="C#"  %>
<%@ Register TagPrefix="dict" 
    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">

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>IPersonalizable</title>
</head>
<body>
    <form id="form1" runat="server">
    <asp:WebPartManager ID="mgr" runat="server" />
    <div>
    <asp:WebPartZone ID="WebPartZone1" runat="server">
      <ZoneTemplate>
        <dict:urllistwebpart id="listwp1" runat="server"
          title="URL List WebPart" />
      </ZoneTemplate>
    </asp:WebPartZone>
    </div>
    </form>
</body>
</html>

<%@ Page Language="VB"  %>
<%@ Register TagPrefix="dict" 
    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">

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>IPersonalizable</title>
</head>
<body>
    <form id="form1" runat="server">
    <asp:WebPartManager ID="mgr" runat="server" />
    <div>
    <asp:WebPartZone ID="WebPartZone1" runat="server">
      <ZoneTemplate>
        <dict:urllistwebpart id="listwp1" runat="server"
          title="URL List WebPart" />
      </ZoneTemplate>
    </asp:WebPartZone>
    </div>
    </form>
</body>
</html>

La seconda parte dell'esempio è il codice per il controllo personalizzato WebPart denominato UrlListWebPart. Questo file deve essere inserito nella directory App_Code per eseguire l'esempio. Si noti che il codice sorgente implementa la IsDirty proprietà .

namespace Samples.AspNet.CS.Controls
{

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

    [AspNetHostingPermission(SecurityAction.Demand,
      Level = AspNetHostingPermissionLevel.Minimal)]
    [AspNetHostingPermission(SecurityAction.InheritanceDemand,
      Level = AspNetHostingPermissionLevel.Minimal)]
    public class UrlListWebPart : WebPart, IPersonalizable
    {
        private ArrayList _sharedUrls;
        private ArrayList _userUrls;
        private bool _listDirty;

        private TextBox _nameTextBox;
        private TextBox _urlTextBox;
        private Button _addButton;
        private BulletedList _list;

        protected override void CreateChildControls()
        {
            Label nameLabel = new Label();
            Label urlLabel = new Label();
            LiteralControl breakLiteral1 = new LiteralControl("<br />");
            LiteralControl breakLiteral2 = new LiteralControl("<br />");
            LiteralControl breakLiteral3 = new LiteralControl("<br />");

            _nameTextBox = new TextBox();
            _urlTextBox = new TextBox();
            _addButton = new Button();
            _list = new BulletedList();

            nameLabel.Text = "Name: ";
            urlLabel.Text = "URL: ";
            _nameTextBox.ID = "nameTextBox";
            _urlTextBox.ID = "urlTextBox";
            _addButton.Text = "Add";
            _addButton.ID = "addButton";
            _addButton.Click += new EventHandler(this.OnClickAddButton);
            _list.DisplayMode = BulletedListDisplayMode.HyperLink;
            _list.ID = "list";

            Controls.Add(nameLabel);
            Controls.Add(_nameTextBox);
            Controls.Add(breakLiteral1);

            Controls.Add(urlLabel);
            Controls.Add(_urlTextBox);
            Controls.Add(breakLiteral2);

            Controls.Add(_addButton);
            Controls.Add(breakLiteral3);

            Controls.Add(_list);
        }

        private void OnClickAddButton(object sender, EventArgs e)
        {
            string name = _nameTextBox.Text.Trim();
            string url = _urlTextBox.Text.Trim();

            Pair p = new Pair(name, url);
            if (WebPartManager.Personalization.Scope == PersonalizationScope.Shared)
            {
                _sharedUrls ??= new ArrayList();
                _sharedUrls.Add(p);
            }
            else
            {
                _userUrls ??= new ArrayList();
                _userUrls.Add(p);
            }

            OnUrlAdded();
        }

        protected virtual void OnUrlAdded()
        {
            _listDirty = true;
            ChildControlsCreated = false;
        }

        protected override void RenderContents(HtmlTextWriter writer)
        {
            if (_sharedUrls != null)
            {
                foreach (Pair p in _sharedUrls)
                {
                    _list.Items.Add(new ListItem((string)p.First, (string)p.Second));
                }
            }
            if (_userUrls != null)
            {
                foreach (Pair p in _userUrls)
                {
                    _list.Items.Add(new ListItem((string)p.First, (string)p.Second));
                }
            }

            base.RenderContents(writer);
        }

        public virtual bool IsDirty
        {
            get
            {
                return _listDirty;
            }
        }
        public new virtual void Load(PersonalizationDictionary state)
        {
            if (state != null)
            {
                PersonalizationEntry sharedUrlsEntry = state["sharedUrls"];
                if (sharedUrlsEntry != null)
                {
                    _sharedUrls = (ArrayList)sharedUrlsEntry.Value;
                }

                PersonalizationEntry userUrlsEntry = state["userUrls"];
                if (userUrlsEntry != null)
                {
                    _userUrls = (ArrayList)userUrlsEntry.Value;
                }
            }
        }

        public virtual void Save(PersonalizationDictionary state)
        {
            if ((_sharedUrls != null) && (_sharedUrls.Count != 0))
            {
                state["sharedUrls"] = new PersonalizationEntry(_sharedUrls, PersonalizationScope.Shared);
            }
            if ((_userUrls != null) && (_userUrls.Count != 0))
            {
                state["userUrls"] = new PersonalizationEntry(_userUrls, PersonalizationScope.User);
            }
        }
    }
}


Imports System.Collections
Imports System.ComponentModel
Imports System.Diagnostics
Imports System.Drawing
Imports System.Web
Imports System.Web.UI
Imports System.Security.Permissions
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 UrlListWebPart
      Inherits WebPart
      Implements IPersonalizable
      Private _sharedUrls As ArrayList
      Private _userUrls As ArrayList
      Private _listDirty As Boolean

      Private _nameTextBox As TextBox
      Private _urlTextBox As TextBox
      Private _addButton As Button
      Private _list As BulletedList


      Protected Overrides Sub CreateChildControls()
          Dim nameLabel As New Label()
          Dim urlLabel As New Label()
          Dim breakLiteral1 As New LiteralControl("<br />")
          Dim breakLiteral2 As New LiteralControl("<br />")
          Dim breakLiteral3 As New LiteralControl("<br />")

          _nameTextBox = New TextBox()
          _urlTextBox = New TextBox()
          _addButton = New Button()
          _list = New BulletedList()

          nameLabel.Text = "Name: "
          urlLabel.Text = "URL: "
          _nameTextBox.ID = "nameTextBox"
          _urlTextBox.ID = "urlTextBox"
          _addButton.Text = "Add"
          _addButton.ID = "addButton"
          AddHandler _addButton.Click, AddressOf Me.OnClickAddButton
          _list.DisplayMode = BulletedListDisplayMode.HyperLink
          _list.ID = "list"

          Controls.Add(nameLabel)
          Controls.Add(_nameTextBox)
          Controls.Add(breakLiteral1)

          Controls.Add(urlLabel)
          Controls.Add(_urlTextBox)
          Controls.Add(breakLiteral2)

          Controls.Add(_addButton)
          Controls.Add(breakLiteral3)

          Controls.Add(_list)

      End Sub


      Private Sub OnClickAddButton(ByVal sender As Object, ByVal e As EventArgs)
          Dim name As String = _nameTextBox.Text.Trim()
          Dim url As String = _urlTextBox.Text.Trim()

          Dim p As New Pair(name, url)
          If WebPartManager.Personalization.Scope = PersonalizationScope.Shared Then
              If _sharedUrls Is Nothing Then
                  _sharedUrls = New ArrayList()
              End If
              _sharedUrls.Add(p)
          Else
              If _userUrls Is Nothing Then
                  _userUrls = New ArrayList()
              End If
              _userUrls.Add(p)
          End If

          OnUrlAdded()

      End Sub


      Protected Overridable Sub OnUrlAdded()
          _listDirty = True
          ChildControlsCreated = False

      End Sub


      Protected Overrides Sub RenderContents(ByVal writer As HtmlTextWriter)
          If Not (_sharedUrls Is Nothing) Then
              Dim p As Pair
              For Each p In _sharedUrls
                  _list.Items.Add(New ListItem(CStr(p.First), CStr(p.Second)))
              Next p
          End If
          If Not (_userUrls Is Nothing) Then
              Dim p As Pair
              For Each p In _userUrls
                  _list.Items.Add(New ListItem(CStr(p.First), CStr(p.Second)))
              Next p
          End If

          MyBase.RenderContents(writer)

      End Sub


      Public Overridable ReadOnly Property IsDirty() As Boolean _
        Implements IPersonalizable.IsDirty
          Get
              Return _listDirty
          End Get
      End Property

      Public Overridable Shadows Sub Load(ByVal state As PersonalizationDictionary) _
        Implements IPersonalizable.Load
          If Not (state Is Nothing) Then
              Dim sharedUrlsEntry As PersonalizationEntry = state("sharedUrls")
              If Not (sharedUrlsEntry Is Nothing) Then
                  _sharedUrls = CType(sharedUrlsEntry.Value, ArrayList)
              End If

              Dim userUrlsEntry As PersonalizationEntry = state("userUrls")
              If Not (userUrlsEntry Is Nothing) Then
                  _userUrls = CType(userUrlsEntry.Value, ArrayList)
              End If
          End If

      End Sub

      Public Overridable Sub Save(ByVal state As PersonalizationDictionary) _
        Implements IPersonalizable.Save
          If Not (_sharedUrls Is Nothing) AndAlso _sharedUrls.Count <> 0 Then
              state("sharedUrls") = New PersonalizationEntry(_sharedUrls, PersonalizationScope.Shared)
          End If
          If Not (_userUrls Is Nothing) AndAlso _userUrls.Count <> 0 Then
              state("userUrls") = New PersonalizationEntry(_userUrls, PersonalizationScope.User)
          End If

      End Sub
  End Class


End Namespace

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Commenti

Quando i dati gestiti da un controllo sono stati modificati, il controllo viene considerato "dirty". Un controllo deve restituire true se i dati personalizzati gestiti tramite l'interfaccia IPersonalizable sono stati modificati. Se un controllo restituisce true da questa proprietà, l'implementazione del metodo di interfaccia del controllo viene chiamata durante l'estrazione del valore della Save proprietà.

Nota

Questa proprietà viene controllata automaticamente dall'infrastruttura di personalizzazione durante le ultime fasi dell'elaborazione di una richiesta POST. Tuttavia, per le richieste GET, il valore restituito dalla IsDirty proprietà non viene controllato. È necessario che un altro evento abbia causato il salvataggio del controllo come "dirty" per qualsiasi stato di controllo, non solo per i dati gestiti da IPersonalizable. Se un controllo può contrassegnarsi come "dirty" durante una richiesta GET o se l'infrastruttura di personalizzazione in alcune condizioni limite molto specifiche considera un controllo "dirty" durante una richiesta GET, Save verrà sempre chiamato .

Un controllo può fare riferimento al controllo associato WebPartManager e controllare la Scope proprietà per determinare l'ambito corrente. Lo stato "dirty" dei dati personalizzati di un controllo deve essere appropriato per l'ambito corrente.

Si applica a