Problem in datagrid

protected void DataGrid1_UpdateCommand(object source, DataGridCommandEventArgs e)
{

    //OleDbConnection con;
    //OleDbCommand cmd;
    try
    {
        OleDbConnection con = new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;data source=d:\\tanu\\database_hardware.mdb;");
        OleDbCommand cmd = new OleDbCommand();
        cmd.CommandText = "UPDATE additem SET name=@name, Item_qty=@Item_qty where Item_id=@Item_id";

        cmd.Parameters.Add("@name", OleDbType.VarChar).Value = ((TextBox)e.Item.Cells[1].Controls[0]).Text;
        cmd.Parameters.Add("@Item_qty", OleDbType.Numeric).Value = ((TextBox)e.Item.Cells[2].Controls[0]).Text;
        cmd.Parameters.Add("@Item_id", OleDbType.Numeric).Value = DataGrid1.DataKeys[e.Item.ItemIndex];

        cmd.Connection = con;
        cmd.Connection.Open();
        cmd.ExecuteNonQuery();
        cmd.Connection.Close();

        DataGrid1.EditItemIndex = -1;
        Binddata();
        
    }
    catch (Exception ex)
    {
        Response.Write(ex.Message);
    }
}