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POWhy is my DropDownList empty on Postback?
 

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  1. POWhy is my DropDownList empty on Postback?
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    <p>I've looked at answers to some similar question but I still can't seem to figure this out. I think I'm misunderstanding something about how ASP.NET works.</p> <p>In the standard ASP.Net 4.0 'Create a new Account' form, I've added a DropDownList containing Roles to be selected for the new account. in the aspx page, the control looks like this:</p> <pre><code>&lt;asp:DropDownList ID="RoleList" Width="100px" runat="server"&gt;&lt;/asp:DropDownList&gt; </code></pre> <p>I am then populating the List in the Page_Load Event:</p> <pre><code>protected void Page_Load(object sender, EventArgs e) { RegisterUser.ContinueDestinationPageUrl = Request.QueryString["ReturnUrl"]; if (Page.IsPostBack) { return; } //Set the Role List Selections DropDownList roleList = (DropDownList)RegisterUser.CreateUserStep.ContentTemplateContainer.FindControl("RoleList"); //set the role list String[] roles = Roles.GetAllRoles(); foreach (String role in roles) { roleList.Items.Add(new ListItem(role, role)); } } </code></pre> <p>I can see/select a role from the generated html. The problem arises when the 'Submit' button for creating a User is clicked:</p> <pre><code>protected void RegisterUser_CreatedUser(object sender, EventArgs e) { FormsAuthentication.SetAuthCookie(RegisterUser.UserName, false /* createPersistentCookie */); string continueUrl = RegisterUser.ContinueDestinationPageUrl; if (String.IsNullOrEmpty(continueUrl)) { continueUrl = "~/"; } //set user role DropDownList roleList = (DropDownList)RegisterUser.CreateUserStep.ContentTemplateContainer.FindControl("RoleList"); Roles.AddUserToRole(RegisterUser.UserName, roleList.SelectedValue); Response.Redirect(continueUrl); } </code></pre> <p>Here, The roleList object contains zero items, and has no selected values. Somehow, I am losing the populating items between selection of the item, and the submit. Any idea what I'm doing wrong?</p>
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    1. USJoel Coehoorn
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      1. USChris
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      1. USKen McAndrew
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    1. This table or related slice is empty.
 

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