protected void GetDepartments()
{
//use EF to connect and get the list of departments
using (DefaultConnection db = new DefaultConnection())
{
var deps = from d in db.Departments
select d;
//bind the deps query result to the grid
grdDepartments.DataSource = deps.ToList();
grdDepartments.DataBind();
}
}
protected void GetStudents()
{
//use EF to connect and get the list of students
using (DefaultConnection db = new DefaultConnection())
{
var studs = from s in db.Students
select s;
//bind the studs query result to our grid
grdStudents.DataSource = studs.ToList();
grdStudents.DataBind();
}
}
protected void GetDepartment()
{
//look up the selected department and fill the form
using (DefaultConnection db = new DefaultConnection())
{
//store the id from the url in a variable
Int32 DepartmentID = Convert.ToInt32(Request.QueryString["DepartmentID"]);
//look up the department
Department dep = (from d in db.Departments
where d.DepartmentID == DepartmentID
select d).FirstOrDefault();
//pre populate the form fields
txtName.Text = dep.Name;
txtBudget.Text = dep.Budget.ToString();
}
}
protected void GetStudent()
{
//look up the selected student and fill the form
using (DefaultConnection db = new DefaultConnection())
{
//store the id from the url in a variable
Int32 StudentID = Convert.ToInt32(Request.QueryString["StudentID"]);
//look up the student
Student stud = (from s in db.Students
where s.StudentID == StudentID
select s).FirstOrDefault();
//pre populate the form fields
txtLastName.Text = stud.LastName;
txtFirstMidName.Text = stud.FirstMidName;
txtEnrollmentDate.Text = stud.EnrollmentDate.ToString("dd-MM-yyyy");
}
}
protected void grdDepartments_RowDeleting(object sender, GridViewDeleteEventArgs e)
{
//identify the department id to be deleted from the row the user selected
Int32 DepartmentID = Convert.ToInt32(grdDepartments.DataKeys[e.RowIndex].Values["DepartmentID"]);
//connect
using (DefaultConnection db = new DefaultConnection())
{
Department dep = (from d in db.Departments
where d.DepartmentID == DepartmentID
select d).FirstOrDefault();
//delete
db.Departments.Remove(dep);
db.SaveChanges();
//refresh the grid
GetDepartments();
}
}
protected void grdStudents_RowDeleting(object sender, GridViewDeleteEventArgs e)
{
//identify the student id to be deleted from the row the user selected
Int32 StudentID = Convert.ToInt32(grdStudents.DataKeys[e.RowIndex].Values["StudentID"]);
//connect
using (DefaultConnection db = new DefaultConnection())
{
Student stud = (from s in db.Students
where s.StudentID == StudentID
select s).FirstOrDefault();
//delete
db.Students.Remove(stud);
db.SaveChanges();
//refresh the grid
GetStudents();
}
}
protected void btnSave_Click(object sender, EventArgs e)
{
//connect to server
using (DefaultConnection db = new DefaultConnection())
{
//Create a new student_details in memory
Student stud = new Student();
Int32 StudentID = 0;
//check for a url
if (!String.IsNullOrEmpty(Request.QueryString["StudentID"]))
{
//get the id from the url
StudentID = Convert.ToInt32(Request.QueryString["StudentID"]);
//look up the student
stud = (from s in db.Students
where s.StudentID == StudentID
select s).FirstOrDefault();
}
//Fill the properties of the new student
stud.LastName = txtLastName.Text;
stud.FirstMidName = txtFirstMidName.Text;
stud.EnrollmentDate = Convert.ToDateTime(txtEnrollmentDate.Text);
//add if we have no id in the url
if (StudentID == 0)
{
db.Students.Add(stud);
}
//save the new student
db.SaveChanges();
//redirect to the students list page
Response.Redirect("students.aspx");
}
}
protected void btnSave_Click(object sender, EventArgs e)
{
//connect to server
using (DefaultConnection db = new DefaultConnection())
{
//Create a new department_details in memory
Department dep = new Department();
Int32 DepartmentID = 0;
//check for a url
if (!String.IsNullOrEmpty(Request.QueryString["DepartmentID"]))
{
//get the id from the url
DepartmentID = Convert.ToInt32(Request.QueryString["DepartmentID"]);
//look up the department
dep = (from d in db.Departments
where d.DepartmentID == DepartmentID
select d).FirstOrDefault();
}
//Fill the properties of the new department
dep.Name = txtName.Text;
dep.Budget = Convert.ToDecimal(txtBudget.Text);
//add if we have no id in the url
if (DepartmentID == 0)
{
db.Departments.Add(dep);
}
//save the new department
db.SaveChanges();
//redirect to the departments list page
Response.Redirect("departments.aspx");
}
}
