view uploded files

hey

i uploaded file in gridview and now i want to view these files i.e when any user click view button then this documnet view in broswer or open in other tab

code

<asp:GridView ID="GridView1" runat="server" CellPadding="4" ForeColor="#333333"
        GridLines="None" AutoGenerateColumns="false" EmptyDataText="no files uploaded"><asp:HyperLink  runat="server" ID="lnkButton" Text="View File" /><RowStyle BackColor="#F7F6F3" ForeColor="#333333" /><FooterStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" /><PagerStyle BackColor="#284775" ForeColor="White" HorizontalAlign="Center" /><SelectedRowStyle BackColor="#E2DED6" Font-Bold="True" ForeColor="#333333" /><HeaderStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" /><EditRowStyle BackColor="#999999" /><AlternatingRowStyle BackColor="White" ForeColor="#284775" /></asp:GridView>

       protected void FileUpload_Click(object sender, EventArgs e)
       {
           if (FileUploadControl.HasFile)
           {
               string strPath = Request.PhysicalApplicationPath + "~/DocFiles/" + FileUploadControl.FileName;
               FileUploadControl.SaveAs(strPath);
               lnkButton.NavigateUrl = "~/DocFiles/" + FileUploadControl.FileName;
           }
       }

   but i find the error in link button

"The name 'lnkButton' does not exist in the current context  " 

where as i call the link button in  grdiview (gridvie  code above)

any help plzzz