protected void RemoveCourseButton_Click(object sender, EventArgs e)
{
using (var context = new SchoolEntities())
{
var instructorID = Convert.ToInt32(InstructorsDropDownList.SelectedValue);
var instructor = (from p in context.People
where p.PersonID == instructorID
select p).First();
var courseID = Convert.ToInt32(AssignedCoursesDropDownList.SelectedValue);
var courses = instructor.Courses;
var courseToRemove = new Course();
foreach (Course c in courses)
{
if (c.CourseID == courseID)
{
courseToRemove = c;
break;
}
}
try
{
courses.Remove(courseToRemove);
context.SaveChanges();
PopulateDropDownLists();
CourseRemovedLabel.Text = "Removal successful.";
}
catch (Exception)
{
CourseRemovedLabel.Text = "Removal unsuccessful.";
//Add code to log the error.
}
CourseRemovedLabel.Visible = true;
}
}
/// <summary>
/// Create a new Course object.
/// </summary>
/// <param name="courseID">Initial value of the CourseID property.</param>
/// <param name="title">Initial value of the Title property.</param>
/// <param name="credits">Initial value of the Credits property.</param>
/// <param name="departmentID">Initial value of the DepartmentID property.</param>
public static Course CreateCourse(global::System.Int32 courseID, global::System.String title, global::System.Int32 credits, global::System.Int32 departmentID)
{
Course course = new Course();
course.CourseID = courseID;
course.Title = title;
course.Credits = credits;
course.DepartmentID = departmentID;
return course;
}
/// <summary>
/// Deprecated Method for adding a new object to the Courses EntitySet. Consider using the .Add method of the associated ObjectSet<T> property instead.
/// </summary>
public void AddToCourses(Course course)
{
base.AddObject("Courses", course);
}