protected void GetCourse()
{
try
{
int courseID = int.Parse(Request.QueryString["CourseID"]);
using (comp2007Entities db = new comp2007Entities())
{
Course course = (from obj in db.Courses where obj.CourseID == courseID select obj).FirstOrDefault();
txtTitle.Text = course.Title;
txtCredits.Text = course.Credits.ToString();
var objS = (from s in db.Students
join e in db.Enrollments on s.StudentID equals e.StudentID
join c in db.Courses on e.CourseID equals c.CourseID
where c.CourseID == courseID
select new { s.StudentID, s.LastName, s.FirstMidName, s.EnrollmentDate, e.EnrollmentID });
grdCourseStudents.DataSource = objS.ToList();
grdCourseStudents.DataBind();
}
}
catch (Exception ex)
{
Response.Redirect("/error.aspx");
}
}
protected void GetDepartment()
{
try
{
int departmentID = int.Parse(Request.QueryString["DepartmentID"]);
using (comp2007Entities db = new comp2007Entities())
{
Department department = (from obj in db.Departments where obj.DepartmentID == departmentID select obj).FirstOrDefault();
txtName.Text = department.Name;
txtBudget.Text = department.Budget.ToString();
var objD = (from d in db.Departments
join c in db.Courses on d.DepartmentID equals c.DepartmentID
where d.DepartmentID == departmentID
select new { c.CourseID, c.Title, c.Credits });
grdDepartmentCourses.DataSource = objD.ToList();
grdDepartmentCourses.DataBind();
}
}
catch (Exception ex)
{
Response.Redirect("/error.aspx");
}
}
protected void GetStudent()
{
try
{
int studentID = int.Parse(Request.QueryString["StudentID"]);
using (comp2007Entities db = new comp2007Entities())
{
Student s = (from objS in db.Students where objS.StudentID == studentID select objS).FirstOrDefault();
txtLastName.Text = s.LastName;
txtFirstMidName.Text = s.FirstMidName;
txtEnrollmentDate.Text = s.EnrollmentDate.ToString("yyyy-mm-dd");
var objE = (from en in db.Enrollments
join c in db.Courses on en.CourseID equals c.CourseID
join d in db.Departments on c.DepartmentID equals d.DepartmentID
where en.StudentID == studentID
select new { en.EnrollmentID, en.Grade, c.Title, d.Name });
grdStudentCourses.DataSource = objE.ToList();
grdStudentCourses.DataBind();
}
}
catch (Exception ex)
{
Response.Redirect("/error.aspx");
}
}
protected void GetStudents()
{
try
{
using (comp2007Entities db = new comp2007Entities())
{
var Students = from s in db.Students
select s;
grdStudents.DataSource = Students.ToList();
grdStudents.DataBind();
}
}
catch (Exception ex)
{
Response.Redirect("/error.aspx");
}
}
protected void GetDepartments()
{
try
{
using (comp2007Entities db = new comp2007Entities())
{
var departments = from d in db.Departments
select d;
grdDepartments.DataSource = departments.ToList();
grdDepartments.DataBind();
}
}
catch (Exception ex)
{
Response.Redirect("/error.aspx");
}
}
protected void GetCourses()
{
try
{
using (comp2007Entities db = new comp2007Entities())
{
string SortString = Session["SortColumn"].ToString();
var courses = from c in db.Courses
select c;
grdCourses.DataSource = courses.AsQueryable().OrderBy(SortString).ToList();
grdCourses.DataBind();
}
}
catch (Exception ex)
{
Response.Redirect("/error.aspx");
}
}
protected void btnSave_Click(object sender, EventArgs e)
{
try
{
//use EF to connect to SQL server
using (comp2007Entities db = new comp2007Entities())
{
//use the Student model to save the new record
Course c = new Course();
int courseID = 0;
if (Request.QueryString["CourseID"] != null)
{
courseID = int.Parse(Request.QueryString["CourseID"]);
c = (from obj in db.Courses where obj.CourseID == courseID select obj).FirstOrDefault();
}
c.Title = txtTitle.Text;
c.Credits = int.Parse(txtCredits.Text);
c.DepartmentID = int.Parse(ddlDepartment.SelectedValue);
if (courseID == 0)
{
db.Courses.Add(c);
}
db.SaveChanges();
//redirect to the updated students page
Response.Redirect("courses.aspx");
}
}
catch (Exception ex)
{
Response.Redirect("/error.aspx");
}
}
protected void btnSave_Click(object sender, EventArgs e)
{
try
{
//use EF to connect to SQL server
using (comp2007Entities db = new comp2007Entities())
{
//use the Student model to save the new record
Student s = new Student();
int studentID = 0;
if (Request.QueryString["StudentID"] != null)
{
studentID = int.Parse(Request.QueryString["StudentID"]);
s = (from objS in db.Students where objS.StudentID == studentID select objS).FirstOrDefault();
}
s.LastName = txtLastName.Text;
s.FirstMidName = txtFirstMidName.Text;
s.EnrollmentDate = DateTime.Parse(txtEnrollmentDate.Text);
if (studentID == 0)
{
db.Students.Add(s);
}
db.SaveChanges();
//redirect to the updated students page
Response.Redirect("students.aspx");
}
}
catch (Exception ex)
{
Response.Redirect("/error.aspx");
}
}
protected void btnSave_Click(object sender, EventArgs e)
{
try
{
//use EF to connect to SQL server
using (comp2007Entities db = new comp2007Entities())
{
//use the Student model to save the new record
Department d = new Department();
int departmentID = 0;
if (Request.QueryString["DepartmentID"] != null)
{
departmentID = int.Parse(Request.QueryString["DepartmentID"]);
d = (from obj in db.Departments where obj.DepartmentID == departmentID select obj).FirstOrDefault();
}
d.Name = txtName.Text;
d.Budget = decimal.Parse(txtBudget.Text);
if (departmentID == 0)
{
db.Departments.Add(d);
}
db.SaveChanges();
//redirect to the updated students page
Response.Redirect("departments.aspx");
}
}
catch (Exception ex)
{
Response.Redirect("/error.aspx");
}
}
protected void grdCourseStudents_RowDeleting(object sender, GridViewDeleteEventArgs e)
{
try
{
int enrollmentID = Convert.ToInt32(grdCourseStudents.DataKeys[e.RowIndex].Values["EnrollmentID"]);
using (comp2007Entities db = new comp2007Entities())
{
var objE = (from en in db.Enrollments
where en.EnrollmentID == enrollmentID
select en).FirstOrDefault();
db.Enrollments.Remove(objE);
db.SaveChanges();
GetCourse();
}
}
catch (Exception ex)
{
Response.Redirect("/error.aspx");
}
}
protected void Page_Load(object sender, EventArgs e)
{
try
{
using (comp2007Entities db = new comp2007Entities())
{
var depts = (from obj in db.Departments select obj);
ddlDepartment.DataSource = depts.ToList();
ddlDepartment.DataTextField = "Name";
ddlDepartment.DataValueField = "DepartmentID";
ddlDepartment.DataBind();
}
if (!IsPostBack && Request.QueryString.Count > 0)
{
GetCourse();
}
}
catch (Exception ex)
{
Response.Redirect("/error.aspx");
}
}
protected void grdCourses_RowDeleting(object sender, GridViewDeleteEventArgs e)
{
try
{
int selectedRow = e.RowIndex;
int courseID = (int)grdCourses.DataKeys[selectedRow].Values["CourseID"];
using (comp2007Entities db = new comp2007Entities())
{
Course c = (from obj in db.Courses where obj.CourseID == courseID select obj).FirstOrDefault();
db.Courses.Remove(c);
db.SaveChanges();
GetCourses();
}
}
catch (Exception ex)
{
Response.Redirect("/error.aspx");
}
}
protected void grdStudents_RowDeleting(object sender, GridViewDeleteEventArgs e)
{
try
{
int selectedRow = e.RowIndex;
int studentID = (int)grdStudents.DataKeys[selectedRow].Values["StudentID"];
using (comp2007Entities db = new comp2007Entities())
{
Student s = (from objS in db.Students where objS.StudentID == studentID select objS).FirstOrDefault();
db.Students.Remove(s);
db.SaveChanges();
GetStudents();
}
}
catch (Exception ex)
{
Response.Redirect("/error.aspx");
}
}
