private void buttonUpdate_Click(object sender, EventArgs e) { List <Subject> subjects = new List <Subject>(); foreach (var item in listBoxSubject.SelectedItems) { var data = (SubjectViewModel)item; Subject sub = new Subject { SubjectId = data.SubjectId, SubjectName = data.SubjectName }; subjects.Add(sub); } List <ClassSectionSubjectViewModel> csSubjectList = new List <ClassSectionSubjectViewModel>(); if (checkBoxAllSection.Checked == true) { var csList = _settingService.GetClassSectionId(((ClassViewModel)comboBoxClass.SelectedItem).ClassId); foreach (var item in csList) { var clssub = new ClassSectionSubjectViewModel { ClassSectionId = item.ClassSectionId, SubjectList = subjects }; csSubjectList.Add(clssub); } } else { var clssub = new ClassSectionSubjectViewModel { ClassSectionId = ((ClassSectionViewModel)comboBoxSection.SelectedItem).ClassSectionId, SubjectList = subjects }; csSubjectList.Add(clssub); } if (_settingService.AssigningSubjetToClassSection(csSubjectList)) { MessageBox.Show("Data Saved Successfully!", "Success", MessageBoxButtons.OK, MessageBoxIcon.Information); } }