Question

Basically, I am trying to put validation control in of Listview. But, I am not able to specify ControlToValidate = “grpNameTextBox”.

I tried to put

((RequiredFieldValidator)ListView1.FindControl("RequiredFieldValidator1")).ControlToValidate = ((TextBox)ListView1.FindControl("grpNameTextBox")).ID;

in different Events, but not able to do it.

Afterwards, I deleted Validation Control, and put simple Label. Then in ‘ItemInserting’ event I put this code :

protected void ListView1_ItemInserting(object sender, ListViewInsertEventArgs e)
    {
        TextBox t1 = (TextBox)ListView1.FindControl("grpNameTextBox"); // Getting Null Exception here
        if (t1.Text.Trim() == null)
        {
            throw new System.Exception("Field cannot be empty");


        }
    }

But getting “Object reference not set to an instance of an object.” error.
Can any one tell me, where I am wrong?

.aspx part is given below :

<InsertItemTemplate>
        <tr style="">
            <td>
                <asp:Button ID="InsertButton" runat="server" CommandName="Insert" 
                    Text="Insert"  />
                <asp:Button ID="CancelButton" runat="server" CommandName="Cancel" 
                    Text="Clear" />
            </td>
            <td>
                &nbsp;</td>
            <td>
                <asp:TextBox ID="grpNameTextBox" runat="server" Text='<%# Bind("grpName") %>' />
                <asp:Label ID="lblError" runat="server" Text=""></asp:Label>
            </td>
        </tr>
    </InsertItemTemplate>

Thanks.

Answer 1

TextBox txt_btn = (TextBox)e.Item.FindControl(“grpNameTextBox”);