![]() TeachersStudents: the junction table to implement the many-to-many relation between Students and Teachers.Teachers with a foreign key to the School they teach on.Students with a foreign key to the School they attend.I describe a database for Schools, where every School has zero or more Students and Teachers (one-to-many), every Student and every Teacher has exactly one Address (one-to-one), Teachers teach zero or more Students, while Students are taught by zero or more teachers (many-to-many) The question describes the classes and the tables, the answer will describe how to do it. Now that I found out how to do it, I decided to jot down how I did it. I found a lot of information about how to do this, but this information was not always helpful, quite often they contradicted each other. the newest version in summer 2020) working together with SQLite (1.0.113.1, also latest in summer 2020). I'm trying to get Entity Framework (6.4.4. I'm not sure whether everything else is okay or not though. Right now I have the error ErrorĜS1061 'Student' does not contain a definition for 'ToList' and no accessible extension method 'ToList' accepting a first argument of type 'Student' could be found (are you missing a using directive or an assembly reference?) when I run it. Now in the post, inside the Model folder, they added an ADO.NET Entity Data Model that connects to the Students table in the database and named it StudentModel while changing connectionstring name to StudentEntities.īut, I have a local SQLite database, how do I change that and what other things I need to change to make this app work? This.DataContext = new StudentViewModel() Propert圜hanged(this, new Propert圜hangedEventArgs(propertyName)) Protected void OnPropert圜hanged(string propertyName) Public event Propert圜hangedEventHandler Propert圜hanged Public class ViewModelBase : INotifyPropert圜hanged ViewModelBase.cs using System.ComponentModel _repository.GetAll().ForEach(data => (new StudentRecord() _studentEntity.stdContact = StudentRecord.Contact _studentEntity.stdAddress = StudentRecord.Address _studentEntity.stdAge = StudentRecord.Age _studentEntity.stdName = StudentRecord.Name MessageBox.Show("Error occured while saving. MessageBox.Show("Record successfully deleted.") If (MessageBox.Show("Confirm delete of this record?", "Student", MessageBoxButton.YesNo) _deleteCommand = new Rela圜ommand(param => DeleteStudent((int)param), null) _editCommand = new Rela圜ommand(param => EditData((int)param), null) _saveCommand = new Rela圜ommand(param => SaveData(), null) _resetCommand = new Rela圜ommand(param => ResetData(), null) Public event EventHandler CanExecuteChangedĪdd Return _canExecute = null ? true : _canExecute(parameter) Throw new ArgumentNullException("execute") Public Rela圜ommand(Action execute, Predicate canExecute) Public ObservableCollection StudentRecords ![]() ![]() Private ObservableCollection _studentRecords Public class StudentRecord : ViewModelBase Var query = "SELECT * FROM tblStud WHERE stdId = args = new student.stdId} Public void RemoveStudent(Student student)Ĭonst string query = "Delete from tblStud WHERE stdId = args = new student.stdId} Public void UpdateStudent(Student student)Ĭonst string query = "UPDATE tblStud SET stdName = stdAge = stdAddress = stdContact = WHERE stdId = args = new student.stdContact} Public DataTable Execute(string query, Dictionary args)Ĭmd.Parameters.AddWithValue(entry.Key, entry.Value) Ĭonst string query = "INSERT INTO tblStud(stdName, stdAge, stdAddress, stdContact) args = new student.stdContact} Using (var cmd = new SQLiteCommand(query, con))Ĭmd.Parameters.AddWithValue(pair.Key, pair.Value) Using (var con = new Source=/.Students.db ")) Public void ExecuteWrite(string query, Dictionary args) Also, for someone who is new to MVVM pattern it seems pretty intimidating to say the least.Īnyways, coming to the point, I've found this post online and tried my best to make it work for SQLite databases but struggling at the moment. I'm totally new to MVVM and I've been going through a lot of online posts regarding how do I implement CRUD operations and properly bind SQLite database data to WPF controls like Datagrid, Combobox, Textbox, Button etc.
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