为什么点击按钮后GridView会消失?

<asp:UpdatePanel ID="upExec" runat="server" ClientIDMode="Static" UpdateMode="Conditional">
    <ContentTemplate>
        <button type="button" runat="server" id="btnExec" onserverclick="btnExec_Click" class="btnAll btnExec">Execute SQL Job</button>
        <asp:Label ID="lblEMsg" runat="server" ClientIDMode="Static" Text=""></asp:Label>
    </ContentTemplate>
</asp:UpdatePanel>
<asp:UpdatePanel ID="upGV" runat="server" ClientIDMode="Static" UpdateMode="Conditional">
    <ContentTemplate>
        <asp:GridView EmptyDataText="No Provider Exists" ID="gvData" runat="server" ClientIDMode="Static" AutoGenerateColumns="false">
            <Columns>
                <asp:BoundField HeaderStyle-Width="5%" DataField="Name" HeaderText="Name" />
                <asp:BoundField HeaderStyle-Width="5%" DataField="ID" HeaderText="ID" />
            </Columns>
        </asp:GridView>
    </ContentTemplate>
</asp:UpdatePanel>
if (!Page.IsPostBack)
{
    ViewState["sortOrder"] = "Asc";
    ViewState["sortExp"] = "Due Date";
    ShowGridView("Name", "Asc");
}
public void ShowGridView(string sortExp, string sortDir)
{
    using (SqlConnection sc = new SqlConnection(gloString))
    {
        try
        {
            sc.Open();
            SqlDataAdapter sda = new SqlDataAdapter(strQuery, sc);
            DataSet ds = new DataSet();
            sda.Fill(ds);
            DataView dv = new DataView();
            dv = ds.Tables[0].DefaultView;
            gvData.DataSource = dv;
            gvData.DataBind();
        }
        catch (SqlException)
        {
        }
        finally
        {
            sc.Close();
        }
    }
    upGV.Update();
}
public void btnExec_Click(object sender, EventArgs e)
{
    using (SqlConnection sc = new SqlConnection(gloString))
    {
        try
        {
            sc.Open();
            using (SqlCommand scd = new SqlCommand())
            {
                scd.CommandText = "MySP";
                scd.CommandType = CommandType.StoredProcedure;
                scd.Connection = sc;
                scd.ExecuteNonQuery();
            }
        }
        catch (SqlException)
        {
        }
        finally
        {
            sc.Close();
        }
    }
    using (SqlConnection sc = new SqlConnection(floString))
    {
        try
        {
            sc.Open();
            SqlCommand scd = new SqlCommand();
            scd.CommandType = CommandType.StoredProcedure;
            scd.Connection = sc;
            scd.CommandText = "msdb.dbo.sp_start_job";
            scd.Parameters.AddWithValue("@job_name", "JobName");
            using (scd)
            {
                scd.ExecuteNonQuery();
                ShowGridView("Name", "Asc");
            }
        }
        catch (SqlException)
        {
        }
        finally
        {
            sc.Close();
        }
    }
    upExec.Update();
}

当页面首次加载时，我可以看到GridView。当我单击btnExec时，GridView消失，并显示"No Provider Exists"。当我检查页面的来源时，数据仍然在那里。

如何解决这个问题，所以当按钮被单击时，它执行存储过程并重新加载GridView与新的数据