protected void GetStudents()
{
try
{
//connect
using (DefaultConnectionEF conn = new DefaultConnectionEF())
{
//use link to query the Students model
var studs = from s in conn.Students
select s;
//If there is a sort parameter then override the query
if (Request.QueryString.Count > 0)
{
studs = from s in conn.Students
orderby Request.QueryString["orderby"]
select s;
}
//bind to the gridview
grdStudents.DataSource = studs.ToList();
grdStudents.DataBind();
}
}
catch (System.IO.IOException e)
{
Server.Transfer("/error.aspx", true);
}
}
protected void btnAdd_Click(object sender, EventArgs e)
{
try
{
using (DefaultConnectionEF conn = new DefaultConnectionEF())
{
//Get the values
Int32 StudentID = Convert.ToInt32(Request.QueryString["StudentID"]);
Int32 CourseID = Convert.ToInt32(ddlCourse.SelectedValue);
//Instantiate the enrollment object
Enrollment objE = new Enrollment();
//Populate, save, and refresh
objE.StudentID = StudentID;
objE.CourseID = CourseID;
conn.Enrollments.Add(objE);
conn.SaveChanges();
GetStudent();
}
}
catch (System.IO.IOException e5)
{
Server.Transfer("/error.aspx", true);
}
}
protected void grdStudents_RowDeleting(object sender, GridViewDeleteEventArgs e)
{
try
{
//connect
using (DefaultConnectionEF conn = new DefaultConnectionEF())
{
//get the Department Id
Int32 StudentID = Convert.ToInt32(grdStudents.DataKeys[e.RowIndex].Values["StudentID"]);
var s = (from stud in conn.Students
where stud.StudentID == StudentID
select stud).FirstOrDefault();
//process the delete
conn.Students.Remove(s);
conn.SaveChanges();
//update the grid
GetStudents();
}
}
catch (System.IO.IOException e2)
{
Server.Transfer("/error.aspx", true);
}
}
protected void btnSave_Click(object sender, EventArgs e)
{
try
{
//connect
using (DefaultConnectionEF conn = new DefaultConnectionEF())
{
//instantiate a new deparment object in memory
Student s = new Student();
//decide if updating and then re-query the updated Students
if (Request.QueryString.Count > 0)
{
Int32 StudentID = Convert.ToInt32(Request.QueryString["StudentID"]);
s = (from stud in conn.Students
where stud.StudentID == StudentID
select stud).FirstOrDefault();
}
//fill in the values
s.FirstMidName = txtFirstMidName.Text;
s.LastName = txtLastName.Text;
s.EnrollmentDate = Convert.ToDateTime(txtEnrollmentDate.Text);
//Only add a new record if it's not updating an existing one
if (Request.QueryString.Count == 0)
{
conn.Students.Add(s);
}
conn.SaveChanges();
//redirect to the Students page
Response.Redirect("students.aspx");
}
}
catch (System.IO.IOException e2)
{
Server.Transfer("/error.aspx", true);
}
}
protected void btnSave_Click(object sender, EventArgs e)
{
try
{
//connect
using (DefaultConnectionEF conn = new DefaultConnectionEF())
{
//instantiate a new deparment object in memory
Department d = new Department();
//decide if updating and then re-query the updated departments
if (Request.QueryString.Count > 0)
{
Int32 DepartmentID = Convert.ToInt32(Request.QueryString["DepartmentID"]);
d = (from dep in conn.Departments
where dep.DepartmentID == DepartmentID
select dep).FirstOrDefault();
}
//fill in the values
d.Name = txtName.Text;
d.Budget = Convert.ToDecimal(txtBudget.Text);
//Only add a new record if it's not updating an existing one
if (Request.QueryString.Count == 0)
{
conn.Departments.Add(d);
}
conn.SaveChanges();
//redirect to the departments page
Response.Redirect("departments.aspx");
}
}
catch (System.IO.IOException e2)
{
Server.Transfer("/error.aspx", true);
}
}
protected void GetDepartments()
{
try
{
//connect
using (DefaultConnectionEF conn = new DefaultConnectionEF())
{
//use link to query the Departments model
var deps = from d in conn.Departments
select d;
//bind to the gridview
grdDepartments.DataSource = deps.ToList();
grdDepartments.DataBind();
}
}
catch (System.IO.IOException e)
{
Server.Transfer("/error.aspx", true);
}
}
protected void GetDepartments()
{
try
{
//connect
using (DefaultConnectionEF conn = new DefaultConnectionEF())
{
var deps = (from d in conn.Departments
orderby d.Name
select d);
//bind to the gridview
ddlDepartments.DataSource = deps.ToList();
ddlDepartments.DataBind();
}
}
catch (System.IO.IOException e)
{
Server.Transfer("/error.aspx", true);
}
}
protected void GetCourses()
{
try
{
//connect
using (DefaultConnectionEF conn = new DefaultConnectionEF())
{
//use link to query the Courses model
var course = from c in conn.Courses
select new { c.CourseID, c.Title, c.Credits, c.Department.Name };
//append the current direction of the sort collumn
String Sort = Session["SortColumn"].ToString() + " " + Session["SortDirection"].ToString();
grdCourses.DataSource = course.AsQueryable().OrderBy(Sort).ToList();
grdCourses.DataBind();
}
}
catch (System.IO.IOException e)
{
Server.Transfer("/error.aspx", true);
}
}
protected void btnSave_Click(object sender, EventArgs e)
{
try
{
//connect
using (DefaultConnectionEF conn = new DefaultConnectionEF())
{
Courses objC = new Courses();
if (!String.IsNullOrEmpty(Request.QueryString["CourseID"]))
{
Int32 CourseID = Convert.ToInt32(Request.QueryString["CourseID"]);
objC = (from c in conn.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(ddlDepartments.SelectedValue);
if (String.IsNullOrEmpty(Request.QueryString["CourseID"]))
{
//add
conn.Courses.Add(objC);
}
conn.SaveChanges();
Response.Redirect("courses.aspx");
}
}
catch (System.IO.IOException e3)
{
Server.Transfer("/error.aspx", true);
}
}
protected void GetDepartment()
{
try
{
//connect
using (DefaultConnectionEF conn = new DefaultConnectionEF())
{
//get id from url parameter and store in a variable
Int32 DepartmentID = Convert.ToInt32(Request.QueryString["DepartmentID"]);
var d = (from dep in conn.Departments
where dep.DepartmentID == DepartmentID
select dep).FirstOrDefault();
//populate the form from our department object
txtName.Text = d.Name;
txtBudget.Text = d.Budget.ToString();
}
}
catch (System.IO.IOException e)
{
Server.Transfer("/error.aspx", true);
}
}
protected void GetCourse()
{
try
{
//connect
using (DefaultConnectionEF conn = new DefaultConnectionEF())
{
Int32 CourseID = Convert.ToInt32(Request.QueryString["CourseID"]);
//use link to query the Courses model
Courses objC = (from c in conn.Courses
where c.CourseID == CourseID
select c).FirstOrDefault();
//bind to the gridview
txtTitle.Text = objC.Title;
txtCredits.Text = objC.Credits.ToString();
}
}
catch (System.IO.IOException e2)
{
Server.Transfer("/error.aspx", true);
}
}
protected void ddlDepartments_SelectedIndexChanged(object sender, EventArgs e)
{
try
{
using (DefaultConnectionEF conn = new DefaultConnectionEF())
{
//store the selected department ID
Int32 DepartmentID = Convert.ToInt32(ddlDepartments.SelectedValue);
var course = (from c in conn.Courses
where c.DepartmentID == DepartmentID
orderby c.Title
select c);
//bind to the ddl
ddlCourse.DataSource = course.ToList();
ddlCourse.DataBind();
//Create a default option
ListItem defaultItem = new ListItem("--Select--", "0");
ddlCourse.Items.Insert(0, defaultItem);
}
}
catch (System.IO.IOException e4)
{
Server.Transfer("/error.aspx", true);
}
}
protected void grdCourses_RowDeleting(object sender, GridViewDeleteEventArgs e)
{
//Get the desired enrollment ID
Int32 EnrollmentID = Convert.ToInt32(grdCourses.DataKeys[e.RowIndex].Values["EnrollmentID"]);
try
{
using (DefaultConnectionEF conn = new DefaultConnectionEF())
{
Enrollment objE = (from en in conn.Enrollments
where en.EnrollmentID == EnrollmentID
select en).FirstOrDefault();
conn.Enrollments.Remove(objE);
conn.SaveChanges();
GetStudent();
}
}
catch (System.IO.IOException e3)
{
Server.Transfer("/error.aspx", true);
}
}
protected void GetStudent()
{
try
{
//connect
using (DefaultConnectionEF conn = new DefaultConnectionEF())
{
//get id from url parameter and store in a variable
Int32 StudentID = Convert.ToInt32(Request.QueryString["StudentID"]);
var s = (from stud in conn.Students
where stud.StudentID == StudentID
select stud).FirstOrDefault();
//populate the form from our Student object
txtFirstMidName.Text = s.FirstMidName;
txtLastName.Text = s.LastName;
txtEnrollmentDate.Text = s.EnrollmentDate.ToString("yyyy-MM-dd");
var studentId = Convert.ToInt32(Request.QueryString["StudentID"]);
var objE = (from en in conn.Enrollments
join c in conn.Courses on en.CourseID equals c.CourseID
join d in conn.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();
//Clear the dropdown
ddlDepartments.ClearSelection();
ddlCourse.ClearSelection();
var deps = (from d in conn.Departments
orderby d.Name
select d);
//bind to the ddl
ddlDepartments.DataSource = deps.ToList();
ddlDepartments.DataBind();
//Create a default option
ListItem defaultItem = new ListItem("--Select--", "0");
ddlDepartments.Items.Insert(0, defaultItem);
ddlCourse.Items.Insert(0, defaultItem);
pnlCourses.Visible = true;
}
}
catch (System.IO.IOException e)
{
Server.Transfer("/error.aspx", true);
}
}
