IPersonalizable.Load(PersonalizationDictionary) Method

Definition

Loads custom data into a control.

public void Load(System.Web.UI.WebControls.WebParts.PersonalizationDictionary state);

Parameters

state
PersonalizationDictionary

A PersonalizationDictionary that contains custom scoped data that was loaded from the underlying data store.

Examples

The following code example demonstrates an implementation of the Load method in a custom WebPart control. For the full code required to run this example, see the Example section in the IPersonalizable class overview.

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);
            }
        }
    }
}

Remarks

This method is called on a control to allow it to load custom data into itself. It can also return a value that indicates whether a control's custom state must be written back to the underlying data store, regardless of whether any other personalization data on the page has changed. A control can set its own custom properties and carry out additional internal logic based on the values contained in the personalization dictionary. This method is called by the Web Parts control set while applying personalization data to a control.

You should also be aware of the merge behavior of User-scoped versus Shared-scoped properties contained in the PersonalizationDictionary object. The state parameter contains a merged representation of custom data that was loaded from the underlying data store. In Shared scope, all the values that were previously added when the page itself was in Shared scope would be available. In User scope, if a value associated with User personalization scope had one value added when the page was in Shared scope, and a different value when the page was in User scope, then the personalization infrastructure would only include the User-scoped value (as opposed to the Shared scope value) within the state parameter.

Applies to

Product Versions
.NET Framework 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1