static void QueryNote()
{
using (var dbContext = new NoteDbContext())
{
var notebooks = dbContext.Notebooks.Where(b => b.Name.StartsWith("programming"));
var notebook = notebooks.FirstOrDefault();
foreach (var note in notebook.Notes)
{
Console.WriteLine(note);
}
var tag = dbContext.Tags.Single(b => b.Name == "ef");
foreach (var note in tag.Notes)
{
Console.WriteLine(note);
}
var utcNow = DateTime.UtcNow;
var createFromThisMonth = new DateTime(utcNow.Year, utcNow.Month, 1, 0, 0, 0, DateTimeKind.Utc);
var notes = dbContext.Notes
.Where(n => n.CreatedUtc >= createFromThisMonth)
.OrderByDescending(n => n.UpdatedUtc);
foreach (var note in notes)
{
Console.WriteLine(note);
}
}
}
static void GetNote(int noteId)
{
using (var dbContext = new NoteDbContext())
{
var note = dbContext.Notes.Find(noteId);
Console.WriteLine(note);
}
}
static void DeleteNote()
{
using (var dbContext = new NoteDbContext())
{
var note = dbContext.Notes.Find(2);
dbContext.Notes.Remove(note);
dbContext.SaveChanges();
}
}
static void QueryNoteWithJoin()
{
using (var dbContext = new NoteDbContext())
{
var notes = from b in dbContext.Notebooks
join n in dbContext.Notes
on b.Id equals n.NotebookId
select new { NoteBookName = b.Name, NoteTitle = n.Title };
foreach (var note in notes)
{
Console.WriteLine($"NoteBookName = {note.NoteBookName}, NoteTitle = {note.NoteTitle}");
}
}
}
static void UpdateNote(int noteId)
{
Console.WriteLine("Before updating");
GetNote(noteId);
using (var dbContext = new NoteDbContext())
{
var note = dbContext.Notes.Find(noteId);
note.Title = "EF configuration Tips";
note.UpdatedUtc = DateTime.UtcNow;
dbContext.SaveChanges();
}
Console.WriteLine("After updating");
GetNote(noteId);
}
static void CreateNote()
{
//Insert a new record with ORM (Entity Framework)
using (var dbContext = new NoteDbContext())
{
// Create notebook
var notebook = new Notebook()
{
Name = "Programming Tips"
};
dbContext.Notebooks.Add(notebook);
// Create tag
var tag = new Tag
{
Name = "ef"
};
dbContext.Tags.Add(tag);
// Crate note
var note = new Note()
{
Title = "EF Tips",
Content = "How to create entity classes from an existing database...",
//CreatedUtc = DateTime.UtcNow,
Notebook = notebook
};
note.Tags.Add(tag);
dbContext.Notes.Add(note);
dbContext.SaveChanges();
Console.WriteLine($"New notebook inserted with Id {notebook.Id}");
Console.WriteLine($"New tag inserted with Id {tag.Id}");
Console.WriteLine($"New note inserted with Id {note.Id}");
}
}
