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PONull Reference Exception when attempting to bind dropdownlist inside formview
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  1. PONull Reference Exception when attempting to bind dropdownlist inside formview
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    copied!<p>I have an edit button and a dropdownlist inside a formview. I am using Linq To Entities to get the data I need to work with and have no problem populating and viewing the formview itemtemplate. </p> <p>However, the dropdownlist control (<code>id="ddlEligibility"</code>) is only in the<code>edititemtemplate</code> (I use a textbox in the <code>itemtemplate</code> to display the current value) and I am having a problem binding this control to the datasource. </p> <p>Specifically, when I click the Edit button I am getting a <code>NullReferenceException - "Object not set to an instance of an object"</code> on the last line of code below. Does anyone have an idea what I am doing wrong?</p> <pre><code>protected void btnEdit_Click(object sender, EventArgs e) { fvSubscriber.ChangeMode(FormViewMode.Edit); fvSubscriber.DataBind(); // Adding this line solved the first problem where I could not find the control LifeLineDSEntities context = new LifeLineDSEntities(): var program = from p in context.EligibilityPrograms select p; DropDownList ddlEligibility = (DropDownList)(fvSubscriber.FindControl("ddlEligibility"))); if (ddlEligibility != null) { ddlEligibility.DataSource = program; ddlEligibility.DataTextField = "ProgramName"; ddlEligibility.DataValueField = "eligibilityCode"; ddlEligibility.DataBind(); statusMessage.InnerHtml = "It is NOT null"; } else { statusMessage.InnerHtml = "It is null"; } } </code></pre> <p>DropDownlist in FormView...</p> <pre><code>&lt;form id="form1" runat="server"&gt; &lt;asp:FormView ID="fvSubscriber" runat="server" RenderOuterTable="false" DefaultMode="Readonly" OnModeChanging="fvSubscriberChanging"&gt; &lt;ItemTemplate&gt; // mark up here &lt;/ItemTemplate&gt; &lt;EditItemTemplate&gt; &lt;asp:DropDownList ID="ddlEligibility" runat="server" /&gt; &lt;/EditItemTemplate&gt; &lt;/asp:FormView&gt; &lt;/form&gt; </code></pre> <p><b>UPDATE:</b> I tried the FindControlRecursive method discussed in the accepted answer in the link below (for FormView though) to see if for some reason the control was not where I thought it was but still no luck, it always comes back null. When I view source on the page, the control "ddlEligibility" is there.</p> <p><a href="https://stackoverflow.com/questions/13336839/asp-net-findcontrol-and-gridview-returning-null">ASP.net .FindControl() and GridView returning null</a></p> <p><b>New Update</b> I was able to find the control by adding fvSubsriber.databind() as shown in the code above, however I am unable to get the edititemtemplate to show the value in the dropdownlist that was displayed in the itemtemplate. In the edititemtemplate is just default to the first item in dropdownlist. I have added the code above. I have moved this new problem to a new post</p>
 

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