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    <p>You could store the bare minimum of what you need to know to recreate the controls in a collection held in session. Session is available during the init phases of the page.</p> <p>Here is an example for you. It consists of: </p> <p>Default.aspx, cs<br> - panel to store user controls<br> - "Add Control Button" which will add a user control each time it is clicked</p> <p>TimeTeller.ascx, cs<br> - has a method called SetTime which sets a label on the control to a specified time.</p> <p>Default.aspx </p> <pre><code>&lt;%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="DynamicControlTest._Default" %&gt; &lt;!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"&gt; &lt;html xmlns="http://www.w3.org/1999/xhtml" &gt; &lt;head runat="server"&gt; &lt;title&gt;&lt;/title&gt; &lt;/head&gt; &lt;body&gt; &lt;form id="form1" runat="server"&gt; &lt;div&gt; &lt;asp:Panel ID="pnlDynamicControls" runat="server"&gt; &lt;/asp:Panel&gt; &lt;br /&gt; &lt;asp:Button ID="btnAddControl" runat="server" Text="Add User Control" onclick="btnAddControl_Click" /&gt; &lt;/div&gt; &lt;/form&gt; &lt;/body&gt; &lt;/html&gt; </code></pre> <p>Default.aspx.cs: </p> <pre><code>using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Web.UI; using System.Web.UI.WebControls; namespace DynamicControlTest { public partial class _Default : System.Web.UI.Page { Dictionary&lt;string, string&gt; myControlList; // ID, Control ascx path protected void Page_Load(object sender, EventArgs e) { } protected override void OnInit(EventArgs e) { base.OnInit(e); if (!IsPostBack) { myControlList = new Dictionary&lt;string, string&gt;(); Session["myControlList"] = myControlList; } else { myControlList = (Dictionary&lt;string, string&gt;)Session["myControlList"]; foreach (var registeredControlID in myControlList.Keys) { UserControl controlToAdd = new UserControl(); controlToAdd = (UserControl)controlToAdd.LoadControl(myControlList[registeredControlID]); controlToAdd.ID = registeredControlID; pnlDynamicControls.Controls.Add(controlToAdd); } } } protected void btnAddControl_Click(object sender, EventArgs e) { UserControl controlToAdd = new UserControl(); controlToAdd = (UserControl)controlToAdd.LoadControl("TimeTeller.ascx"); // Set a value to prove viewstate is working ((TimeTeller)controlToAdd).SetTime(DateTime.Now); controlToAdd.ID = Guid.NewGuid().ToString(); // does not have to be a guid, just something unique to avoid name collision. pnlDynamicControls.Controls.Add(controlToAdd); myControlList.Add(controlToAdd.ID, controlToAdd.AppRelativeVirtualPath); } } } </code></pre> <p>TimeTeller.ascx</p> <pre><code>&lt;%@ Control Language="C#" AutoEventWireup="true" CodeBehind="TimeTeller.ascx.cs" Inherits="DynamicControlTest.TimeTeller" %&gt; &lt;asp:Label ID="lblTime" runat="server"/&gt; </code></pre> <p>TimeTeller.ascx.cs </p> <pre><code>using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Web.UI; using System.Web.UI.WebControls; namespace DynamicControlTest { public partial class TimeTeller : System.Web.UI.UserControl { protected void Page_Load(object sender, EventArgs e) { } public void SetTime(DateTime time) { lblTime.Text = time.ToString(); } protected override void LoadViewState(object savedState) { base.LoadViewState(savedState); lblTime.Text = (string)ViewState["lblTime"]; } protected override object SaveViewState() { ViewState["lblTime"] = lblTime.Text; return base.SaveViewState(); } } } </code></pre> <p>As you can see, I still have to manage the internal viewstate of my user control, but the viewstate bag is being saved to the page and handed back to the control on postback. I think it is important to note that my solution is very close to David's. The only major difference in my example is that it's using session instead of viewstate to store the control info. This allows things to happen during the initialization phase. It is important to note that this solution takes up more server resources, therefore it may not be appropriate in some situations depending on your scaling strategy. </p>
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    1. POHow can I re-instantiate dynamic ASP.NET user controls without using a database?
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    1. POHow can I re-instantiate dynamic ASP.NET user controls without using a database?
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    1. COI like that idea, because all I'm really concerned with is the id's (and perhaps the order) of the controls I'm trying to load. I'll work up a quick test bed for that solution and get back to you. Thanks!
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    2. COI hope you are able to get it to work. I've had to do something similar in the past. It's best to get the controls back on the page in the init phase because that's the way control lifecycle is expected to play out. I'm sure David's solution works, but I'd be concerned about long term maintainability. I've done things like that as well and it eventually turns into a "fighting the framework" scenario. You may eventually run into something that just won't work if you add it that late on in the lifecycle.
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    3. CODaniel, I've made some progress with using your session solution but I've hit two snags. One is that despite the fact that the controls are being readded in the Init() stage the View State isn't being restored. I was under the impression that all I need to set on the dynamic control when it's being readded is the correct ID to get the View State data back, is there something I'm missing? Also, the session data persists even if I'm not using a post-back. I would just set the Session to null when !Page.IsPostBack, but the flag doesn't get set until after the Init() stage.
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