ASP.net .FindControl() and GridView returning null

I have looked over the pages on the site, but cant seem to find something general enough for my problem, so was hoping someone knows what to do. I am debugging some code someone else wrote and am having problems with a GridView statement.

My problem is that my gridview is always null. I have a declared GridView in a panel which is in a LoginView, which is basically set up as the following.

<asp:LoginView ID="LoginView1" runat="server" onviewchanged="LoginView1_ViewChanged">
<AnonymousTemplate>&nbsp;Please <a href="../Default.aspx" rel="nofollow noreferrer noopener"> Log In </a></AnonymousTemplate>
<LoggedInTemplate>
        <asp:Panel ID="Panel1" runat="server">
            <asp:GridView ID="GridView1" runat="server" 
                AutoGenerateColumns="False" CellPadding="2" 
                DataSourceID="SqlDataSource1" ForeColor="Black" GridLines="Horizontal" 
                BackColor="White" BorderColor="#CCCCCC" BorderStyle="None" 
                BorderWidth="1px" Width="970px" OnRowCommand="GridView1_RowCommand" 
                PageSize="40" AllowSorting="True">

After that, in a C# file, I have the following statement

   GridView GridView1 = (GridView)LoginView1.FindControl("GridView1");

When I go to run the code, I get the NullRefrenceException on GridView1. Do I need to dig down into the panel to refrence the GridView, or should I be able to access it from the main LoginView1 segment?

Edit:Changed my code snippet to include the information for the Anonymous Template

Here is Solutions:

We have many solutions to this problem, But we recommend you to use the first solution because it is tested & true solution that will 100% work for you.

Solution 1

Finding the controls of a child control is an issue that comes up a lot. You can consider an extension method so you can easily call Jeff Atwood’s recursive child control (as referenced in Simon’s answer)… or whatever version of it you write. This is just an example using the code from that other post:

GridView GridView1 = (GridView)LoginView1.FindControlRecursive("GridView1");

Here’s the code.

public static class WebControlExtender
    {
        public static Control FindControlRecursive(this Control root, string id)
        {
            if (root.ID == id)
            {
                return root;
            }

            foreach (Control c in root.Controls)
            {
                Control t = FindControlRecursive(c, id);
                if (t != null)
                {
                    return t;
                }
            }

            return null;
        } 
    }

Solution 2

FindControl will only check direct descendants of the control you’re using it on. It won’t work recursively through the childrens-children.

Jeff Atwood actually blogged about this aaaaggeesss ago:

http://www.codinghorror.com/blog/2005/06/recursive-pagefindcontrol.html

Note: Use and implement solution 1 because this method fully tested our system.
Thank you 🙂

All methods was sourced from stackoverflow.com or stackexchange.com, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0

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