protected void GridViewAllAttendance_RowUpdating(object sender, GridViewUpdateEventArgs e) { GridViewRow gvr = GridViewAllAttendance.Rows[e.RowIndex]; var attID = int.Parse(GridViewAllAttendance.DataKeys[e.RowIndex].Values[0].ToString()); var attendanceToUpdate = ac.GetAllAttendance().Where(x => x.id == attID).FirstOrDefault(); TextBox att = (TextBox)gvr.FindControl("TextBoxAttendance"); if (attendanceToUpdate != null) { if (att.Text == "False") { attendanceToUpdate.Attendance1 = false; ac.UpdateAttendance(attendanceToUpdate); } else if (att.Text == "True") { attendanceToUpdate.Attendance1 = true; ac.UpdateAttendance(attendanceToUpdate); } e.Cancel = true; GridViewAllAttendance.EditIndex = -1; BindGrid(); } }