Question

I have a GridView which has the property:

OnRowUpdating="GridViewRowUpdateEventHandler"

Within the GridView, I have the following control:

<asp:TemplateField HeaderText="Progress" SortExpression="progress">
    <ItemTemplate>
        <asp:DropDownList ID="DropDownList1" runat="server" AutoPostBack="true">
            <asp:ListItem Value="0">Incomplete</asp:ListItem>
            <asp:ListItem Value="1">Complete</asp:ListItem>
        </asp:DropDownList>
    </ItemTemplate>
</asp:TemplateField> 

The GridViewRowUpdateEventHandler looks like this:

protected void GridViewRowUpdateEventHandler(object sender, GridViewUpdateEventArgs e)
{
    SqlConnection connection;
    SqlCommand command;

    GridViewRow row = (GridViewRow)GridView1.Rows[e.RowIndex];

    DropDownList ddlPriority = (DropDownList)row.FindControl("DropDownList1");

    using (connection = new SqlConnection(ConfigurationManager.AppSettings["connString"]))
    {
        using (command = new SqlCommand(@"update table1 set priority = @priority where id = @id", connection))
        {
            command.Parameters.Add("@priority", SqlDbType.Int, 1).Value = ddlPriority.SelectedValue;
            command.Parameters.Add("@id", SqlDbType.Int, 1).Value = row.RowIndex;

            connection.Open();
            command.ExecuteNonQuery();
            connection.Close();
        }
    }

    GridView1.DataBind();
}

I am getting no error messages at all, and the relevant row in the database is not being updated. Anyone know why?

Could it be that I am looking at the wrong cell Cells[5]? Or maybe because I have nothing in page_load? Or maybe something else?

Answer 1

Since the DropDiownList is in a TemplateField and it’s NamingContainer is the GridViewRow, you should use row.FindControl to get the reference:

DropDownList ddlPriority = (DropDownList)row.FindControl("DropDownList1");

instead of

DropDownList ddlPriority = (DropDownList)row.Cells[5].FindControl("DropDownList1");

But that is not the core of your problem since row.Cells[5].FindControl might work also when it is in the 6th cell. Otherwise you would get a NullreferenceException.

I assume that you are also binding the GridView on postbacks, you should check the IsPostBack property:

protected void Page_Load()
{
    if (!IsPostBack)
    {
        BindGrid();
    }
}

Apart from that:

command.Parameters.Add("@id", SqlDbType.Int, 1).Value = row;

Does not work because row is the GridViewRow. You should also DataBind your GridView at the end, otherwise the changes won’t be reflected.