private EmployeeShiftPresets ConvertShiftToShiftPreset(EmployeeShift shift)
 {
     return new EmployeeShiftPresets() { StartTime = shift.StartTime, EmployeeLevelCategory = shift.EmployeeShiftCategory, FinishTime = shift.EndTime };
 }
 private void button4_Click(object sender, EventArgs e)
 {
     var newshift = new EmployeeShift() { StartTime = dateTimePicker2.Value, EmployeeShiftCategory = new EmployeeLevelCategory() { MinLevelStaffMember = 5, Name = "SSS" } };
     if (checkBox1.Checked)
     {
         newshift.EndTime = dateTimePicker3.Value;
     }
     else
     {
         newshift.EndTime = null;
     }
     ShiftSlots.Add(newshift);
     RebindShiftSlots();
 }