/// <summary> /// This method gets the Students data from the DB /// </summary> private void GetStudentsDetails() { int StudentID = Convert.ToInt32(Request.QueryString["StudentID"]); // Connect to Entity FrameWork using (ControlsoContext db = new ControlsoContext()) { //Query the Students Table using EF and LINQ var Students = (from allStudents in db.Students where allStudents.StudentID == StudentID select allStudents); // bind the result to the Student GridView StudentGridView.DataSource = Students.ToList(); StudentGridView.DataBind(); //Query the Course Table using EF and LINQ var CoursesDetails = (from allCourse in db.Courses join enrolment in db.Enrollments on allCourse.CourseID equals enrolment.CourseID where enrolment.StudentID == StudentID select new { CourseID = allCourse.CourseID, Title = allCourse.Title, Grade = enrolment.Grade, Credit = allCourse.Credits }); // bind the result to the Course GridView StudentCourseView.DataSource = CoursesDetails.ToList(); StudentCourseView.DataBind(); } }
protected void CourseDetails_RowDeleting(object sender, GridViewDeleteEventArgs e) { // Store Which row need to be deleted int selectedRow = e.RowIndex; // get the seleceted Enrollment Id int EnrollmentID = Convert.ToInt32(CourseDetails.DataKeys[selectedRow].Values["EnrollmentID"]); using (ControlsoContext db = new ControlsoContext()) { var deleteStudent = (from delStudent in db.Enrollments where delStudent.EnrollmentID == EnrollmentID select delStudent); // Remove Student from Enrolmented course foreach (var item in deleteStudent) { db.Enrollments.Remove(item); } db.SaveChanges(); // Refresh the Grid this.GetStudents(); } }
/// <summary> /// This method gets the Students data from the DB /// </summary> private void GetStudents() { // Connect to Entity FrameWork using (ControlsoContext db = new ControlsoContext()) { //Query the Students Table using EF and LINQ var Students = (from allStudents in db.Students select allStudents); // bind the result to the Student GridView StudentGridView.DataSource = Students.ToList(); StudentGridView.DataBind(); } }
private void GetStudents() { int CourseID = Convert.ToInt32(Request.QueryString["CourseID"]); // using (ControlsoContext db = new ControlsoContext()) { // query the Student table using EF and LINQ var Students = (from allStudents in db.Students join enrollment in db.Enrollments on allStudents.StudentID equals enrollment.StudentID where enrollment.CourseID == CourseID select new { LastName = allStudents.LastName, FirstMidName = allStudents.FirstMidName, EnrollmentID = enrollment.EnrollmentID }); CourseDetails.DataSource = Students.ToList(); CourseDetails.DataBind(); } }
protected void SaveButton_Click(object sender, EventArgs e) { //use EF to conect to the server using (ControlsoContext db = new ControlsoContext()) { //use the student model to create a new students object and // save a new record Enrollment addStudent = new Enrollment(); int EnrollmentID = 0; if (Request.QueryString.Count > 0)//our URL has a StudentID in it { // get the id from the URL /*StudentID = Convert.ToInt32(Request.QueryString["StudentID"]); * //get the Current student from EF bd * newStudent = (from student in db.Students * where student.StudentID == StudentID * select student).FirstOrDefault();*/ } // add form data th the new student record addStudent.CourseID = Convert.ToInt32(CourseIDTextBox.Text); addStudent.StudentID = Convert.ToInt32(StudentIDTextBox.Text); addStudent.Grade = Convert.ToInt32(GradeTextBox.Text); //use LINQ to ADO.NET to add / insert students into the db if (EnrollmentID == 0) { db.Enrollments.Add(addStudent); } //save our changes -also updates and inserts db.SaveChanges(); // Redirect back to the update Students page Response.Redirect("Default.aspx"); } }
protected void GetStudent() { //populated the form with existing data from db int StudentID = Convert.ToInt32(Request.QueryString["StudentID"]); //Connect to the EF DB using (ControlsoContext db = new ControlsoContext()) { // populate a student object instance with the studentID // from the url parameter Student updateStudent = (from student in db.Students where student.StudentID == StudentID select student).FirstOrDefault(); // map the student properties to the form control if (updateStudent != null) { LastNameTextBox.Text = updateStudent.LastName; FirstNameTextbox.Text = updateStudent.FirstMidName; EnrollmentDateTextbox.Text = updateStudent.EnrollmentDate.ToString("yyyy-MM-dd"); } } }