private void ClassroomSaveButton_Click(object sender, EventArgs e) { try { if (String.IsNullOrEmpty(buildingTextBox.Text)) { MessageBox.Show("please enter builing name"); return; } if (String.IsNullOrEmpty(roomNumberTexBox.Text)) { MessageBox.Show("Please enter room number"); return; } if (String.IsNullOrEmpty(capacityTexBox.Text)) { MessageBox.Show("Please enter only numeric value"); return; } if (System.Text.RegularExpressions.Regex.IsMatch(capacityTexBox.Text, "[^0-9]")) { MessageBox.Show("Please enter a numeric capacity"); capacityTexBox.Text = capacityTexBox.Text.Remove(capacityTexBox.Text.Length - 1); return; } Classroom classroom = new Classroom(); classroom.Building = buildingTextBox.Text; classroom.Room_Number = roomNumberTexBox.Text; classroom.Capacity = Convert.ToDouble(capacityTexBox.Text); string existOrInsert = classRoomManager.IsExistOrInsert(classroom); if (!String.IsNullOrEmpty(existOrInsert)) { MessageBox.Show(existOrInsert); } else { MessageBox.Show("Data Insert successfull !"); } } catch (Exception ex) { } }