how can i get the value of hidden field in grid view?

Question

the order number of hidden field in grid view is 7.

when i click the button the line

string sValue = ((HiddenField)GridView1.SelectedRow.Cells[7].FindControl("HiddenField1")).Value; 

gives error which is "Object reference not set to an instance of an object."

          <asp:TemplateField>
            <ItemTemplate> 

                <asp:HiddenField ID="HiddenField1" runat="server" 
                    Value='<%#Eval("RSS_ID")%>'/>

            </ItemTemplate>
          </asp:TemplateField>

c# side

else if (e.CommandName == "View")
{
    string sValue = ((HiddenField)GridView1.SelectedRow.Cells[7].FindControl("HiddenField1")).Value;                   
}

Answer 1

did you try this?

HiddenField field = (HiddenField)GridView.Rows[GridView.SelectedIndex].FindControl("HiddenField1");

If yes, how about this one?

HiddenField field = GridView1.Rows[e.RowIndex].FindControl("HiddenField1") as HiddenField;

Here is another one you could try,

if(e.Row.RowType == DataControlRowType.DataRow)
{    
     HiddenField field = e.Row.FindControl("HiddenField1") as HiddenField;
}

Hope this helps...cheers