protected void GetCourse()
{
//populate the existing course for editing
using (comp2007Entities db = new comp2007Entities())
{
Int32 CourseID = Convert.ToInt32(Request.QueryString["CourseID"]);
Course objC = (from c in db.Courses
where c.CourseID == CourseID
select c).FirstOrDefault();
//populate the form
txtTitle.Text = objC.Title;
txtCredits.Text = objC.Credits.ToString();
ddlDepartment.SelectedValue = objC.DepartmentID.ToString();
var objS = (from s in db.Students
join en in db.Enrollments on s.StudentID equals en.StudentID
join c in db.Courses on en.CourseID equals c.CourseID
where c.CourseID == CourseID
select new { s.StudentID, s.LastName, s.FirstMidName, s.EnrollmentDate });
grdStudents.DataSource = objS.ToList();
grdStudents.DataBind();
}
}
protected void GetStudent()
{
Int32 StudentID = Convert.ToInt32(Request.QueryString["StudentID"]);
using (comp2007Entities db = new comp2007Entities())
{
Student s = (from ObjS in db.Students where ObjS.StudentID == StudentID select ObjS).FirstOrDefault();
//map the student properties to form controls
if (s != null)
{
txtLastName.Text = s.LastName;
txtFirstName.Text = s.FirstMidName;
txtEnrollmentDate.Text = s.EnrollmentDate.ToString("yyyy-MM-dd");
pnlCourses.Visible = true;
}
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 == s.StudentID
select new { en.EnrollmentID, d.Name, c.Title, en.Grade });
grdStudent.DataSource = objE.ToList();
grdStudent.DataBind();
}
}
protected void btnSave_Click(object sender, EventArgs e)
{
using (comp2007Entities db = new comp2007Entities())
{
//use the student model to save record
Department d = new Department();
Int32 DepartmentID = 0;
//check query string for an id so we can determine add or update
if (Request.QueryString["DepartmentID"] != null)
{
DepartmentID = Convert.ToInt32(Request.QueryString["DepartmentID"]);
//get the current student from EF
d = (from objD in db.Departments where objD.DepartmentID == DepartmentID select objD).FirstOrDefault();
}
d.Name = txtName.Text;
d.Budget = Convert.ToDecimal(txtBudget.Text);
//redirect to updated table of students
if (DepartmentID == 0)
{
db.Departments.Add(d);
}
db.SaveChanges();
Response.Redirect("departments.aspx");
}
}
protected void btnSave_Click(object sender, EventArgs e)
{
//do insert or update
using (comp2007Entities db = new comp2007Entities())
{
Course objC = new Course();
if (!String.IsNullOrEmpty(Request.QueryString["CourseID"]))
{
Int32 CourseID = Convert.ToInt32(Request.QueryString["CourseID"]);
objC = (from c in db.Courses
where c.CourseID == CourseID
select c).FirstOrDefault();
}
//populate the course from the input form
objC.Title = txtTitle.Text;
objC.Credits = Convert.ToInt32(txtCredits.Text);
objC.DepartmentID = Convert.ToInt32(ddlDepartment.SelectedValue);
if (String.IsNullOrEmpty(Request.QueryString["CourseID"]))
{
//add
db.Courses.Add(objC);
}
//save and redirect
db.SaveChanges();
Response.Redirect("courses.aspx");
}
}
protected void GetStudent()
{
//populate form with existing student record
Int32 StudentID = Convert.ToInt32(Request.QueryString["StudentID"]);
//connect to db via EF
using (comp2007Entities db = new comp2007Entities())
{
//populate a student instance with the StudentID from the URL parameter
Student s = (from objS in db.Students
where objS.StudentID == StudentID
select objS).FirstOrDefault();
//map the student properties to the form controls if we found a match
if (s != null)
{
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});
grdCourses.DataSource = objE.ToList();
grdCourses.DataBind();
}
}
protected void btnSave_Click(object sender, EventArgs e)
{
using (comp2007Entities db = new comp2007Entities())
{
//use the student model to save record
Student s = new Student();
Enrollment en = new Enrollment();
Int32 StudentID = 0;
//check query string for an id so we can determine add or update
if (Request.QueryString["StudentID"] != null)
{
StudentID = Convert.ToInt32(Request.QueryString["StudentID"]);
//get the current student from EF
s = (from objS in db.Students where objS.StudentID == StudentID select objS).FirstOrDefault();
}
s.LastName = txtLastName.Text;
s.FirstMidName = txtFirstName.Text;
s.EnrollmentDate = Convert.ToDateTime(txtEnrollmentDate.Text);
//add only if student has no ID
if (StudentID == 0)
{
//redirect to updated table of students
db.Students.Add(s);
}
db.SaveChanges();
Response.Redirect("students.aspx");
}
}
protected void GetDepartments()
{
using (comp2007Entities db = new comp2007Entities())
{
var deps = (from d in db.Departments
orderby d.Name
select d);
ddlDepartment.DataSource = deps.ToList();
ddlDepartment.DataBind();
}
}
protected void GetDepartments()
{
using (comp2007Entities db = new comp2007Entities())
{
String sortString = Session["SortColumn"].ToString() + " " + Session["SortDirection"].ToString();
var Departments = from d in db.Departments
select d;
//bind results
grdDepartments.DataSource = Departments.AsQueryable().OrderBy(sortString).ToList();
grdDepartments.DataBind();
}
}
protected void GetCourses()
{
using (comp2007Entities db = new comp2007Entities())
{
String sortString = Session["SortColumn"].ToString() + " " + Session["SortDirection"].ToString();
var Courses = from c in db.Courses
select new { c.CourseID, c.Title, c.Credits, c.Department.Name };
//bind results
grdCourses.DataSource = Courses.AsQueryable().OrderBy(sortString).ToList();
grdCourses.DataBind();
}
}
protected void grdStudent_RowDeleting(object sender, GridViewDeleteEventArgs e)
{
Int32 EnrollmentID = Convert.ToInt32(grdStudent.DataKeys[e.RowIndex].Values["EnrollmentID"]);
using (comp2007Entities db = new comp2007Entities())
{
Enrollment objE = (from en in db.Enrollments
where en.EnrollmentID == EnrollmentID
select en).FirstOrDefault();
db.Enrollments.Remove(objE);
db.SaveChanges();
GetStudent();
}
}
protected void grdCourse_RowDeleting(object sender, GridViewDeleteEventArgs e)
{
Int32 CourseID = Convert.ToInt32(grdCourse.DataKeys[e.RowIndex].Values["CourseID"]);
using (comp2007Entities db = new comp2007Entities())
{
Course objE = (from en in db.Courses
where en.CourseID == CourseID
select en).FirstOrDefault();
db.Courses.Remove(objE);
db.SaveChanges();
GetDepartment();
}
}
protected void grdCourses_RowDeleting(object sender, GridViewDeleteEventArgs e)
{
//store the row clicked
Int32 selectedRow = e.RowIndex;
//get the selected StudentID
Int32 CourseID = Convert.ToInt32(grdCourses.DataKeys[selectedRow].Values["CourseID"]);
//using EF to remove selected student
using (comp2007Entities db = new comp2007Entities())
{
Course c = (from objC in db.Courses where objC.CourseID == CourseID select objC).FirstOrDefault();
db.Courses.Remove(c);
db.SaveChanges();
}
//refresh grid
GetCourses();
}
protected void GetCourses()
{
//connect to EF
using (comp2007Entities db = new comp2007Entities())
{
//query the courses table using EF and LINQ
var Course = from c in db.Courses
select new {c.CourseID, c.Title, c.Credits, c.Department.Name};
//apend the current direction to the sort column
String SortString = Session["SortColumn"].ToString() + " " + Session["SortDirection"].ToString();
//bind the result to the gridview
grdCourses.DataSource = Course.AsQueryable().OrderBy(SortString).ToList();
grdCourses.DataBind();
}
}
protected void GetStudents()
{
//connect to EF
using (comp2007Entities db = new comp2007Entities())
{
//query the students table using EF and LINQ
var Students = from s in db.Students
select s;
//apend the current direction to the sort column
String SortString = Session["SortColumn"].ToString() + " " + Session["SortDirection"].ToString();
//bind the result to the gridview
grdStudents.DataSource = Students.AsQueryable().OrderBy(SortString).ToList();
grdStudents.DataBind();
}
}
protected void btnSave_Click(object sender, EventArgs e)
{
//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();
Int32 StudentID = 0;
//check the querystring for an id so we can determine add / update
if (Request.QueryString["StudentID"] != null)
{
//get the id from the url
StudentID = Convert.ToInt32(Request.QueryString["StudentID"]);
//get the current student from EF
s = (from objS in db.Students
where objS.StudentID == StudentID
select objS).FirstOrDefault();
}
s.LastName = txtLastName.Text;
s.FirstMidName = txtFirstMidName.Text;
s.EnrollmentDate = Convert.ToDateTime(txtEnrollmentDate.Text);
//call add only if we have no student ID
if (StudentID == 0)
{
db.Students.Add(s);
}
//run the update or insert
db.SaveChanges();
//redirect to the updated students page
Response.Redirect("students.aspx");
}
}
protected void GetDepartment()
{
Int32 DepartmentID = Convert.ToInt32(Request.QueryString["DepartmentID"]);
using (comp2007Entities db = new comp2007Entities())
{
Department d = (from ObjD in db.Departments where ObjD.DepartmentID == DepartmentID select ObjD).FirstOrDefault();
if (d != null)
{
//map the student properties to form controls
txtName.Text = d.Name;
txtBudget.Text = d.Budget.ToString();
pnlCourse.Visible = true;
}
var objE = (from c in db.Courses
where c.DepartmentID == d.DepartmentID
select new { c.CourseID, d.Name, c.Title, c.Credits });
grdCourse.DataSource = objE.ToList();
grdCourse.DataBind();
}
}
protected void grdStudents_RowDeleting(object sender, GridViewDeleteEventArgs e)
{
//store which row was clicked
Int32 selectedRow = e.RowIndex;
//get the selected StudentID using the grid's Data Key collection
Int32 StudentID = Convert.ToInt32(grdStudents.DataKeys[selectedRow].Values["StudentID"]);
//use EF to remove the selected student from the db
using (comp2007Entities db = new comp2007Entities())
{
Student s = (from objS in db.Students
where objS.StudentID == StudentID
select objS).FirstOrDefault();
//do the delete
db.Students.Remove(s);
db.SaveChanges();
}
//refresh the grid
GetStudents();
}
protected void grdDepartments_RowDeleting(object sender, GridViewDeleteEventArgs e)
{
//store the row clicked
Int32 selectedRow = e.RowIndex;
//get the selected StudentID
Int32 DepartmentID = Convert.ToInt32(grdDepartments.DataKeys[selectedRow].Values["DepartmentID"]);
//using EF to remove selected student
using (comp2007Entities db = new comp2007Entities())
{
Department d = (from objD in db.Departments where objD.DepartmentID == DepartmentID select objD).FirstOrDefault();
db.Departments.Remove(d);
db.SaveChanges();
}
//refresh grid
GetDepartments();
}
protected void grdStudents_RowDeleting(object sender, GridViewDeleteEventArgs e)
{
Int32 StudentID = Convert.ToInt32(grdStudents.DataKeys[e.RowIndex].Values["StudentID"]);
using (comp2007Entities db = new comp2007Entities())
{
//get selected record
Student objE = (from s in db.Students
where s.StudentID == StudentID
select s).FirstOrDefault();
//Delete
db.Students.Remove(objE);
db.SaveChanges();
//Refresh the data on the page
GetCourse();
}
}
