private static async Task UpdateAsync(BooksContext context, Book book, string user)
{
try
{
Console.WriteLine($"{user}: updating id {book.BookId}, " + $"timestamp: {book.TimeStamp}");
ShowChanges(book.BookId, context.Entry(book));
int records = await context.SaveChangesAsync();
Console.WriteLine($"{user}: updated {book.TimeStamp}");
Console.WriteLine($"{user}: {records} record(s) updated while updating " + $"{book.Title}");
}
catch (DbUpdateConcurrencyException ex)
{
Console.WriteLine($"{user}: update failed with {book.Title}");
Console.WriteLine($"error: {ex.Message}");
foreach (var entry in ex.Entries)
{
Book b = entry.Entity as Book;
Console.WriteLine($"{b.Title} {b.TimeStamp}");
ShowChanges(book.BookId, context.Entry(book));
}
}
Console.WriteLine($"successfully written to the database: id {book.BookId} with title {book.Title}");
}
private static async Task UpdateAsync(BooksContext context, Book book, string user)
{
try
{
WriteLine($"{user}: updating id {book.BookId}, timestamp {book.TimeStamp.StringOutput()}");
ShowChanges(book.BookId, context.Entry(book));
int records = await context.SaveChangesAsync();
WriteLine($"{user}: updated {book.TimeStamp.StringOutput()}");
WriteLine($"{user}: {records} record(s) updated while updating {book.Title}");
}
catch (DbUpdateConcurrencyException ex)
{
WriteLine($"{user} update failed with {book.Title}");
WriteLine($"{user} error: {ex.Message}");
foreach (var entry in ex.Entries)
{
Book b = entry.Entity as Book;
WriteLine($"{b.Title} {b.TimeStamp.StringOutput()}");
ShowChanges(book.BookId, context.Entry(book));
}
}
}
private async Task AddBooksAsync()
{
using (BooksContext context = new BooksContext())
{
Book book = new Book
{
Title = "Professional C# 5 and .NET 4.5.1",
Publisher = "Wrox Press"
};
Book book1 = new Book
{
Title = "Professional C# 2012 and .NET 4.5",
Publisher = "Wrox Press"
};
Book book2 = new Book
{
Title = "JavaScript for Kids",
Publisher = "Wrox Press"
};
Book book3 = new Book
{
Title = "Web Design with HTML and CSS",
Publisher = "Wrox Press"
};
context.AddRange(book, book1, book2, book3);
// context.Add(book);
int records = await context.SaveChangesAsync();
Console.WriteLine($"{records} record added");
}
}
private async Task AddBooksAsync()
{
using (var context = new BooksContext())
{
var b1 = new Book {
Title = "Professional C# 5 and .NET 4.5.1", Publisher = "Wrox Press"
};
var b2 = new Book {
Title = "Professional C# 2012 and .NET 4.5", Publisher = "Wrox Press"
};
var b3 = new Book {
Title = "JavaScript for Kids", Publisher = "Wrox Press"
};
var b4 = new Book {
Title = "Web Design with HTML and CSS", Publisher = "For Dummies"
};
var b5 = new Book {
Title = "Conflict Handling", Publisher = "Test"
};
context.AddRange(b1, b2, b3, b4, b5);
int records = await context.SaveChangesAsync();
WriteLine($"{records} records added");
}
WriteLine();
}
private async Task AddBookAsync(string title, string publisher)
{
using (var context = new BooksContext())
{
var book = new Book { Title = title, Publisher = publisher };
context.Add(book);
int records = await context.SaveChangesAsync();
WriteLine($"{records} record added");
}
WriteLine();
}
private async Task DeleteBooksAsync()
{
using (var context = new BooksContext())
{
var books = context.Books;
context.Books.RemoveRange(books);
int records = await context.SaveChangesAsync();
WriteLine($"{records} records deleted");
}
WriteLine();
}
private async Task AddBookAsync(string title, string publisher)
{
Console.WriteLine(nameof(AddBookAsync));
using var context = new BooksContext();
var book = new Book(title, publisher);
await context.Books.AddAsync(book);
int records = await context.SaveChangesAsync();
Console.WriteLine($"{records} record added");
Console.WriteLine();
}
private static async Task AddBookAsync()
{
using (var context = new BooksContext())
{
var b = new Book { Title = BookTitle, Publisher = "Sample" };
context.Add(b);
int records = await context.SaveChangesAsync();
WriteLine($"{records} record added");
}
WriteLine();
}
private async Task AddBookAsync(string title, string publisher)
{
using (var context = new BooksContext())
{
var book = new Book {
Title = title, Publisher = publisher
};
context.Add(book);
int records = await context.SaveChangesAsync();
WriteLine($"{records} record added");
}
WriteLine();
}
private async Task UpdateBookAsync()
{
int records = 0;
using (BooksContext context = new BooksContext()) {
var book = context.Books.Where(c => c.Title == "上下五千年").FirstOrDefault();
if (book != null)
{
book.Title = "Conflict Handling";
book.Publisher = "Mr e zhon Tian";
records = await context.SaveChangesAsync();
}
}
Console.WriteLine($"{records} record updated ");
}
private static async Task AddBookAsync()
{
using (var context = new BooksContext())
{
var b = new Book {
Title = BookTitle, Publisher = "Sample"
};
context.Add(b);
int records = await context.SaveChangesAsync();
WriteLine($"{records} record added");
}
WriteLine();
}
private async Task DeleteBookAsync(int id)
{
using var context = new BooksContext();
Book b = await context.Books.FindAsync(id);
if (b == null)
{
return;
}
context.Books.Remove(b);
int records = await context.SaveChangesAsync();
Console.WriteLine($"{records} books deleted");
Console.WriteLine();
}
private async Task UpdateBookAsync()
{
using (var context = new BooksContext())
{
int records = 0;
var book = context.Books.Where(b => b.Title == "Professional C# 6").FirstOrDefault();
if (book != null)
{
book.Title = "Professional C# 6 and .NET Core 5";
records = await context.SaveChangesAsync();
}
WriteLine($"{records} record updated");
}
WriteLine();
}
private async Task AddBooksAsync()
{
using (var context = new BooksContext())
{
var b1 = new Book { Title = "Professional C# 5 and .NET 4.5.1", Publisher = "Wrox Press" };
var b2 = new Book { Title = "Professional C# 2012 and .NET 4.5", Publisher = "Wrox Press" };
var b3 = new Book { Title = "JavaScript for Kids", Publisher = "Wrox Press" };
var b4 = new Book { Title = "Web Design with HTML and CSS", Publisher = "For Dummies" };
var b5 = new Book { Title = "Conflict Handling", Publisher = "Test" };
context.AddRange(b1, b2, b3, b4, b5);
int records = await context.SaveChangesAsync();
WriteLine($"{records} records added");
}
WriteLine();
}
private async Task UpdateBookAsync()
{
using var context = new BooksContext();
int records = 0;
Book book = await context.Books
.Where(b => b.Title == "Professional C# 7")
.FirstOrDefaultAsync();
if (book != null)
{
book.Title = "Professional C# 7 and .NET Core 2.0";
records = await context.SaveChangesAsync();
}
Console.WriteLine($"{records} record updated");
Console.WriteLine();
}
public async Task AddBooksAsync()
{
var b1 = new Book {
Title = "Professional C# 5 and .NET 4.5.1", Publisher = "Wrox Press"
};
var b2 = new Book {
Title = "Professional C# 2012 and .NET 4.5", Publisher = "Wrox Press"
};
var b3 = new Book {
Title = "JavaScript for Kids", Publisher = "Wrox Press"
};
var b4 = new Book {
Title = "Web Design with HTML and CSS", Publisher = "For Dummies"
};
_booksContext.AddRange(b1, b2, b3, b4);
int records = await _booksContext.SaveChangesAsync();
WriteLine($"{records} records added");
}
private async Task AddBooksAsync()
{
Console.WriteLine(nameof(AddBooksAsync));
using (var context = new BooksContext())
{
var b1 = new Book("Professional C# 6 and .NET Core 1.0", "Wrox Press");
var b2 = new Book("Professional C# 5 and .NET 4.5.1", "Wrox Press");
var b3 = new Book("JavaScript for Kids", "Wrox Press");
var b4 = new Book("HTML and CSS", "John Wiley");
await context.Books.AddRangeAsync(b1, b2, b3, b4);
var a1 = new Author("Christian", "Nagel");
var a2 = new Author("Jay", "Glynn");
var a3 = new Author("Jon", "Duckett");
var a4 = new Author("Nick", "Morgan");
await context.Authors.AddRangeAsync(a1, a2, a3, a4);
var ba1 = new BookAuthor {
Author = a1, Book = b1
};
var ba2 = new BookAuthor {
Author = a1, Book = b2
};
var ba3 = new BookAuthor {
Author = a2, Book = b2
};
var ba4 = new BookAuthor {
Author = a3, Book = b4
};
var ba5 = new BookAuthor {
Author = a4, Book = b3
};
await context.BookAuthors.AddRangeAsync(ba1, ba2, ba3, ba4, ba5);
int records = await context.SaveChangesAsync();
Console.WriteLine($"{records} records added");
}
Console.WriteLine();
}
private async Task DeleteAllBookAsync()
{
using (var context = new BooksContext())
{
var books = await context.Books.ToListAsync();
if (books == null)
{
return;
}
Console.WriteLine($"{books.Count} books found");
for (var i = 0; i < books.Count; i++)
{
var b = books[i];
context.Books.Remove(b);
int records = await context.SaveChangesAsync();
Console.WriteLine($"{records} books deleted");
}
}
Console.WriteLine();
}
private async Task UpdateBookAsync()
{
using (var context = new BooksContext())
{
int records = 0;
var book = context.Books.Where(b => b.Title == "Professional C# 6").FirstOrDefault();
if (book != null)
{
book.Title = "Professional C# 6 and .NET Core 5";
records = await context.SaveChangesAsync();
}
WriteLine($"{records} record updated");
}
WriteLine();
}
private static async Task UpdateAsync(BooksContext context, Book book)
{
await context.SaveChangesAsync();
WriteLine($"successfully written to the database: id {book.BookId} with title {book.Title}");
}
private static async Task UpdateAsync(BooksContext context, Book book)
{
await context.SaveChangesAsync();
WriteLine($"successfully written to the database: id {book.BookId} with title {book.Title}");
}
private async Task DeleteBooksAsync()
{
using (var context = new BooksContext())
{
var books = context.Books;
context.Books.RemoveRange(books);
int records = await context.SaveChangesAsync();
WriteLine($"{records} records deleted");
}
WriteLine();
}
private static async Task UpdateAsync(BooksContext context, Book book, string user)
{
try
{
WriteLine($"{user}: updating id {book.BookId}, timestamp {book.TimeStamp.StringOutput()}");
ShowChanges(book.BookId, context.Entry(book));
int records = await context.SaveChangesAsync();
WriteLine($"{user}: updated {book.TimeStamp.StringOutput()}");
WriteLine($"{user}: {records} record(s) updated while updating {book.Title}");
}
catch (DbUpdateConcurrencyException ex)
{
WriteLine($"{user} update failed with {book.Title}");
WriteLine($"{user} error: {ex.Message}");
foreach (var entry in ex.Entries)
{
Book b = entry.Entity as Book;
WriteLine($"{b.Title} {b.TimeStamp.StringOutput()}");
ShowChanges(book.BookId, context.Entry(book));
}
}
}