<pre name="code" class="csharp">public class Student : RaiseBase
{
private StDataSet.studentRow studentrow;
public StDataSet.studentRow Studentrow
{
get { return studentrow; }
}
public int StuID
{
get
{
return xkzdatarow.stuID;
}
}
public string Sname
{
get
{
return studentrow.sname;
}
set
{
if (studentrow.sname != value)
{
studentrow.sname = value;
RaisePropertyChanged("Sname");
}
}
}
public int Age
{
get
{
return studentrow.age;
}
set
{
if (studentrow.age != value)
{
studentrow.age = value;
RaisePropertyChanged("Age");
}
}
}
public bool IsNew { get; set; }
public int GetMaxStuID()
{
object obj = DataRepository.GetInstance().sda.GetMaxStuID();
if (obj == null)
{
return 1;
}
else
{
return int.Parse(obj.ToString());
}
}
public void SetNewStuID()
{
studentrow.stuID = GetMaxStuID();
}
public static Student GetFromDataRow(StDataSet.studentRow _studentrow)
{
return new Student()
{
studentrow = _studentrow,
IsNew = false,
};
}
public Student(bool isNew)
{
studentrow = DataRepository.GetInstance().tbSudents.NewstudentRow();
IsNew = isNew;
<span style="white-space:pre"> </span>studentrow.sname = "";
<span style="white-space:pre"> </span>studentrow.age = 0;
}
public Student()
{
}
}
public class DataRepository
{
private static DataRepository _instance;
public StDataSet stDataSet;
public StDataSetTableAdapters.studentTableAdapter sda;
public static DataRepository GetInstance()
{
if (_instance == null)
{
_instance = new DataRepository();
}
return _instance;
}
private DataRepository()
{
this.LoadData();
}
public StDataSet.studentDataTable tbStudents
{
get { return stDataSet.student; }
}
public IEnumerable<Student> GetStudents()
{
foreach (StDataSet.studentRow dataRow in tbStudents.Rows)
{
yield return Student.GetFromDataRow(dataRow);
}
}
public void SaveStudent(Student student)
{
if (student.IsNew)
{
AddStudent(student);
}
else
{
sda.Update(student.Studentrow);
}
}
private void AddStudent(Student student)
{
tbStudents.Rows.Add(student.Studentrow);
sda.Update(student.Studentrow);
}
public void DeleteStudent(Student student)
{
sda.Delete(student.Studentrow);
}
private void LoadData()
{
stDataSet = new StDataSet();
sda = new StDataSetTableAdapters.studentTableAdapter();
sda.Fill(stDataSet.student);
}
private void DisposeData()
{
stDataSet.student.Dispose();
stDataSet.Dispose();
}
public void Exit()
{
DisposeData();
_instance = null;
}
}
}
public class DisplayStudentViewModel : ViewModelBase
{
private Student _displayedStudent;
public Student DisplayedStudent
{
get { return _displayedStudent; }
set
{
if (_displayedStudent != value)
{
_displayedStudent = value;
RaisePropertyChanged("DisplayedStudent");
RaisePropertyChanged("IsSelected");
}
}
}
public bool IsSelected
{
get { return (DisplayedStudent != null); }
}
private ObservableCollection<Student> students;
public ObservableCollection<Student> Students
{
get
{
if (students == null)
{
students = new ObservableCollection<Student>();
foreach (var student in DataRepository.GetInstance().GetStudents())
{
students.Add(student);
}
}
return students;
}
}
enum EditModeType
{
DefaultMode, //非编辑模式
AddNewMode, //添加
EditMode, //修改
BgMode, //变更
ZxMode //注销
}
EditModeType _editModeType;
private EditModeType editModeType
{
get { return _editModeType; }
set { _editModeType = value; }
}
private RelayCommand _addNewCommand;
private RelayCommand _editCommand;
private RelayCommand _updateCommand;
private RelayCommand _deleteCommand;
private RelayCommand _saveCommand;
private RelayCommand _cancelCommand;
private RelayCommand _exitCommand;
public DisplayStudentViewModel()
{
editModeType = EditModeType.DefaultMode;
}
public ICommand AddCommand
{
get
{
if (this._addNewCommand == null)
{
this._addNewCommand = new RelayCommand(AddNew,CanAddNew);
}
return this._addNewCommand;
}
}
public ICommand EditCommand
{
get
{
if (this._editCommand == null)
{
this._editCommand = new RelayCommand(Edit,CanEdit);
}
return this._editCommand;
}
}
public ICommand UpdateCommand
{
get
{
if (this._updateCommand == null)
{
this._updateCommand = new RelayCommand(Update,CanUpdate);
}
return this._updateCommand;
}
}
public ICommand DeleteCommand
{
get
{
if (this._deleteCommand == null)
{
this._deleteCommand = new RelayCommand(Delete,CanDelete);
}
return this._deleteCommand;
}
}
public ICommand SaveCommand
{
get
{
if (this._saveCommand == null)
{
this._saveCommand = new RelayCommand(Save,CanSave);
}
return this._saveCommand;
}
}
public ICommand CancelCommand
{
get
{
if (this._cancelCommand == null)
{
this._cancelCommand = new RelayCommand(Cancel,CanCancel);
}
return this._cancelCommand;
}
}
public ICommand ExitCommand
{
get
{
if (this._exitCommand == null)
{
this._exitCommand = new RelayCommand(Exit, CanExit);
}
return this._exitCommand;
}
}
void AddNew(object obj)
{
DisplayedStudent = new Student(true);
editModeType = EditModeType.AddNewMode;
}
bool CanAddNew(object obj)
{
return (IsDefaultMode());
}
void Edit(object obj)
{
editModeType = EditModeType.EditMode;
}
bool CanEdit(object obj)
{
return (IsDefaultMode()) && IsSelected;
}
void Update(object obj)
{
editModeType = EditModeType.BgMode;
}
bool CanUpdate(object obj)
{
return (IsDefaultMode()) && IsSelected;
}
void Cancel(object obj)
{
CancelEdit();//略
editModeType = EditModeType.DefaultMode;
}
bool CanCancel(object obj)
{
return !IsDefaultMode();
}
void Save(object obj)
{
if (!SaveStudent())
{
return;
}
editModeType = EditModeType.DefaultMode;
}
bool SaveStudent()
{
if (editModeType == EditModeType.AddNewMode)
{
try
{
DataRepository.GetInstance().SaveStudent(DisplayedStudent);
DisplayedStudent.IsNew = false;
DisplayedStudent.SetNewStuID();
Students.Add(DisplayedStudent);
return true;
}
catch { return false; }
}
else if (editModeType == EditModeType.EditMode)
{
try
{
DataRepository.GetInstance().SaveStudent(DisplayedStudent);
return true;
}
catch { return false; }
}
else if (editModeType == EditModeType.BgMode)
{
try
{
DataRepository.GetInstance().SaveStudent(DisplayedStudent);//变更数据保存程序略
return true;
}
catch { return false; }
}
else
try
{
DataRepository.GetInstance().DeleteStudent(DisplayedStudent);
Students.Remove(DisplayedStudent);
return true;
}
catch { return false; }
}
bool CanSave(object obj)
{
return !IsDefaultMode();
}
void Delete(object obj)
{
editModeType = EditModeType.ZxMode;
}
bool CanDelete(object obj) { return (IsDefaultMode()) && IsSelected; }
void Exit(object obj)
{
DataRepository.GetInstance().Exit();
App.Current.Shutdown();
}
bool CanExit(object obj) { return (IsDefaultMode()); }
private bool IsDefaultMode()
{
return editModeType == EditModeType.DefaultMode;
}
}
时间： 2024-08-30 11:00:59