public void CreateUser(UserCreationSpec userToCreate)
{
if (userToCreate == null)
{
throw new ArgumentNullException("userToCreate");
}
userToCreate.Validate();
/*
* Typical usage of DbContextScope for a read-write business transaction.
* It's as simple as it looks.
*/
using (var dbContextScope = _dbContextScopeFactory.Create())
{
//-- Build domain model
var user = new User()
{
Id = userToCreate.Id,
Name = userToCreate.Name,
Email = userToCreate.Email,
WelcomeEmailSent = false,
CreatedOn = DateTime.UtcNow
};
//-- Persist
_userRepository.Add(user);
dbContextScope.SaveChanges();
}
}
public void Update_user_CreditScore_for_all_users_in_parallel_should_work()
{
var johnSpec = new UserCreationSpec("John", "*****@*****.**");
var jeanneSpec = new UserCreationSpec("Jeanne", "*****@*****.**");
var julieSpec = new UserCreationSpec("Julie", "*****@*****.**");
var marcSpec = new UserCreationSpec("Marc", "*****@*****.**");
var marysSpec = new UserCreationSpec("Mary", "*****@*****.**");
UserCreationService.CreateListOfUsers(johnSpec, jeanneSpec, julieSpec, marcSpec, marysSpec);
var scoresBefore = UserQueryService.GetUsers(johnSpec.Id, jeanneSpec.Id, julieSpec.Id, marcSpec.Id, marysSpec.Id)
.Select(u => u.CreditScore)
.ToArray();
Assert.AreEqual(5, scoresBefore.Length);
Array.ForEach(scoresBefore, s => Assert.AreEqual(0, s));
UserCreditScoreService.UpdateCreditScoreForAllUsers();
var scoresAfter = UserQueryService.GetUsers(johnSpec.Id, jeanneSpec.Id, julieSpec.Id, marcSpec.Id, marysSpec.Id)
.Select(u => u.CreditScore)
.ToArray();
Assert.AreEqual(5, scoresAfter.Length);
Array.ForEach(scoresAfter, s => Assert.AreNotEqual(0, s));
}
public void Update_user_in_nested_but_isolated_transaction_should_work()
{
var johnSpec = new UserCreationSpec("John", "*****@*****.**");
UserCreationService.CreateUser(johnSpec);
using (var parentScope = DBContextScopeFactory.Create())
{
var parentDbContext = parentScope.Get <TestDbContext>();
// Load John in the parent DbContext
var john = parentDbContext.Users.Find(johnSpec.Id);
Assert.IsFalse(john.WelcomeEmailSent);
// Now call our SendWelcomeEmail() business logic service method, which will
// update John in a non-nested child context
UserEmailService.SendWelcomeEmail(johnSpec.Id);
Assert.IsTrue(john.WelcomeEmailSent);
// Note that even though we're not calling SaveChanges() in the parent scope here, the changes
// made to John by SendWelcomeEmail() will remain persisted in the database as SendWelcomeEmail()
// forced the creation of a new DbContextScope.
}
}
public void CreateUser(UserCreationSpec userToCreate)
{
if (userToCreate == null)
throw new ArgumentNullException("userToCreate");
userToCreate.Validate();
/*
* Typical usage of DbScope for a read-write business transaction.
* It's as simple as it looks.
*/
using (var dbScope = _dbScopeFactory.Create())
{
//-- Build domain model
var user = new User
{
Id = userToCreate.Id,
Name = userToCreate.Name,
Email = userToCreate.Email,
WelcomeEmailSent = false,
CreatedOn = DateTime.UtcNow
};
//-- Persist
_userRepository.Add(user);
dbScope.SaveChanges();
}
}
public static void Equal(this UserCreationSpec spec, User user)
{
Assert.NotNull(spec);
Assert.NotNull(user);
Assert.Equal(spec.Id, user.Id);
Assert.Equal(spec.Email, user.Email);
Assert.Equal(spec.Name, user.Name);
}
public void Create_and_retrieve_user_should_work()
{
var marysSpec = new UserCreationSpec("Mary", "*****@*****.**");
UserCreationService.CreateUser(marysSpec);
var mary = UserQueryService.GetUser(marysSpec.Id);
Assert.IsNotNull(mary);
}
public void Retrieve_user_within_read_uncommited_transaction_should_work()
{
var johnSpec = new UserCreationSpec("John", "*****@*****.**");
UserCreationService.CreateUser(johnSpec);
var userMaybeUncommitted = UserQueryService.GetUserUncommitted(johnSpec.Id);
Assert.IsNotNull(userMaybeUncommitted);
}
public async Task Get_users_in_async_fashion_should_work()
{
var johnSpec = new UserCreationSpec("John", "*****@*****.**");
var jeanneSpec = new UserCreationSpec("Jeanne", "*****@*****.**");
UserCreationService.CreateListOfUsers(johnSpec, jeanneSpec);
var usersFoundAsync = await UserQueryService.GetTwoUsersAsync(johnSpec.Id, jeanneSpec.Id);
Assert.AreEqual(2, usersFoundAsync.Count);
}
public void Create_list_of_users_in_failing_atomic_transation_should_not_save_anything_at_all()
{
var julieSpec = new UserCreationSpec("Julie", "*****@*****.**");
var marcSpec = new UserCreationSpec("Marc", "*****@*****.**");
Assert.ThrowsException <Exception>(() => UserCreationService.CreateListOfUsersWithIntentionalFailure(julieSpec, marcSpec));
var maybeCreatedUsers = UserQueryService.GetUsers(julieSpec.Id, marcSpec.Id);
Assert.AreEqual(0, maybeCreatedUsers.Count());
}
public void Create_list_of_users_and_count_users_should_work()
{
var johnSpec = new UserCreationSpec("John", "*****@*****.**");
var jeanneSpec = new UserCreationSpec("Jeanne", "*****@*****.**");
UserCreationService.CreateListOfUsers(johnSpec, jeanneSpec);
var createdUsers = UserQueryService.GetUsers(johnSpec.Id, jeanneSpec.Id);
Assert.AreEqual(2, createdUsers.Count());
}
static void Main(string[] args)
{
//-- Poor-man DI - build our dependencies by hand for this demo
var dbContextScopeFactory = new DbContextScopeFactory();
var ambientDbContextLocator = new AmbientDbContextLocator();
var userRepository = new UserRepository(ambientDbContextLocator);
var userCreationService = new UserCreationService(dbContextScopeFactory, userRepository);
var userQueryService = new UserQueryService(dbContextScopeFactory, userRepository);
var userEmailService = new UserEmailService(dbContextScopeFactory);
var userCreditScoreService = new UserCreditScoreService(dbContextScopeFactory);
try
{
Console.WriteLine("This demo application will create a database named DbContextScopeDemo in the default SQL Server instance on localhost. Edit the connection string in UserManagementDbContext if you'd like to create it somewhere else.");
Console.WriteLine("Press enter to start...");
Console.ReadLine();
//-- Demo of typical usage for read and writes
Console.WriteLine("Creating a user called Mary...");
var marysSpec = new UserCreationSpec("Mary", "*****@*****.**");
userCreationService.CreateUser(marysSpec);
Console.WriteLine("Done.\n");
Console.WriteLine("Trying to retrieve our newly created user from the data store...");
var mary = userQueryService.GetUser(marysSpec.Id);
Console.WriteLine("OK. Persisted user: {0}", mary);
Console.WriteLine("Press enter to continue...");
Console.ReadLine();
//-- Demo of nested DbContextScopes
Console.WriteLine("Creating 2 new users called John and Jeanne in an atomic transaction...");
var johnSpec = new UserCreationSpec("John", "*****@*****.**");
var jeanneSpec = new UserCreationSpec("Jeanne", "*****@*****.**");
userCreationService.CreateListOfUsers(johnSpec, jeanneSpec);
Console.WriteLine("Done.\n");
Console.WriteLine("Trying to retrieve our newly created users from the data store...");
var createdUsers = userQueryService.GetUsers(johnSpec.Id, jeanneSpec.Id);
Console.WriteLine("OK. Found {0} persisted users.", createdUsers.Count());
Console.WriteLine("Press enter to continue...");
Console.ReadLine();
//-- Demo of nested DbContextScopes in the face of an exception.
// If any of the provided users failed to get persisted, none should get persisted.
Console.WriteLine("Creating 2 new users called Julie and Marc in an atomic transaction. Will make the persistence of the second user fail intentionally in order to test the atomicity of the transaction...");
var julieSpec = new UserCreationSpec("Julie", "*****@*****.**");
var marcSpec = new UserCreationSpec("Marc", "*****@*****.**");
try
{
userCreationService.CreateListOfUsersWithIntentionalFailure(julieSpec, marcSpec);
Console.WriteLine("Done.\n");
}
catch (Exception e)
{
Console.WriteLine(e.Message);
Console.WriteLine();
}
Console.WriteLine("Trying to retrieve our newly created users from the data store...");
var maybeCreatedUsers = userQueryService.GetUsers(julieSpec.Id, marcSpec.Id);
Console.WriteLine("Found {0} persisted users. If this number is 0, we're all good. If this number is not 0, we have a big problem.", maybeCreatedUsers.Count());
Console.WriteLine("Press enter to continue...");
Console.ReadLine();
//-- Demo of DbContextScope within an async flow
Console.WriteLine("Trying to retrieve two users John and Jeanne sequentially in an asynchronous manner...");
// We're going to block on the async task here as we don't have a choice. No risk of deadlocking in any case as console apps
// don't have a synchronization context.
var usersFoundAsync = userQueryService.GetTwoUsersAsync(johnSpec.Id, jeanneSpec.Id).Result;
Console.WriteLine("OK. Found {0} persisted users.", usersFoundAsync.Count());
Console.WriteLine("Press enter to continue...");
Console.ReadLine();
//-- Demo of explicit database transaction.
Console.WriteLine("Trying to retrieve user John within a READ UNCOMMITTED database transaction...");
// You'll want to use SQL Profiler or Entity Framework Profiler to verify that the correct transaction isolation
// level is being used.
var userMaybeUncommitted = userQueryService.GetUserUncommitted(johnSpec.Id);
Console.WriteLine("OK. User found: {0}", userMaybeUncommitted);
Console.WriteLine("Press enter to continue...");
Console.ReadLine();
//-- Demo of disabling the DbContextScope nesting behaviour in order to force the persistence of changes made to entities
// This is a pretty advanced feature that you can safely ignore until you actually need it.
Console.WriteLine("Will simulate sending a Welcome email to John...");
using (var parentScope = dbContextScopeFactory.Create())
{
var parentDbContext = parentScope.DbContexts.Get <UserManagementDbContext>();
// Load John in the parent DbContext
var john = parentDbContext.Users.Find(johnSpec.Id);
Console.WriteLine("Before calling SendWelcomeEmail(), john.WelcomeEmailSent = " + john.WelcomeEmailSent);
// Now call our SendWelcomeEmail() business logic service method, which will
// update John in a non-nested child context
userEmailService.SendWelcomeEmail(johnSpec.Id);
// Verify that we can see the modifications made to John by the SendWelcomeEmail() method
Console.WriteLine("After calling SendWelcomeEmail(), john.WelcomeEmailSent = " + john.WelcomeEmailSent);
// Note that even though we're not calling SaveChanges() in the parent scope here, the changes
// made to John by SendWelcomeEmail() will remain persisted in the database as SendWelcomeEmail()
// forced the creation of a new DbContextScope.
}
Console.WriteLine("Press enter to continue...");
Console.ReadLine();
//-- Demonstration of DbContextScope and parallel programming
Console.WriteLine("Calculating and storing the credit score of all users in the database in parallel...");
userCreditScoreService.UpdateCreditScoreForAllUsers();
Console.WriteLine("Done.");
}
catch (Exception e)
{
Console.WriteLine(e);
}
Console.WriteLine();
Console.WriteLine("The end.");
Console.WriteLine("Press enter to exit...");
Console.ReadLine();
}
private static void Main(string[] args)
{
//-- Poor-man DI - build our dependencies by hand for this demo
ISessionFactory sessionFactory = UserSessionFactory.CreateSessionFactory();
ISessionScopeFactory sessionScopeFactory = new SessionScopeFactory(sessionFactory);
IAmbientSessionLocator ambientSessionLocator = new AmbientSessionLocator();
IUserRepository userRepository = new UserRepository(ambientSessionLocator);
var userCreationService = new UserCreationService(sessionScopeFactory, userRepository);
var userQueryService = new UserQueryService(sessionScopeFactory, userRepository);
var userCreditScoreService = new UserCreditScoreService(sessionScopeFactory);
try
{
Console.WriteLine("This demo application will create a database named NH in the LocalDB SQL Server instance on localhost. Edit the connection string in UserSessionFactory if you'd like to create it somewhere else.");
Console.WriteLine("Press enter to start...");
Console.ReadLine();
//-- Demo of typical usage for read and writes
Console.WriteLine("Creating a user called Mary...");
var marySpec = new UserCreationSpec("Mary", "*****@*****.**");
userCreationService.CreateUser(marySpec);
Console.WriteLine("Done.\n");
Console.WriteLine("Trying to retrieve our newly created user from the data store...");
var mary = userQueryService.GetUser(marySpec.Id);
Console.WriteLine("OK. Persisted user: {0}", mary);
Console.WriteLine("Trying to retrieve our newly created user from the data store via a repository...");
var maryViaRepo = userQueryService.GetUserViaRepository(marySpec.Id);
Console.WriteLine("OK. Persisted user: {0}", maryViaRepo);
Console.WriteLine("Press enter to continue...");
Console.ReadLine();
//-- Demo of nested SessionScopes
Console.WriteLine("Creating 2 new users called John and Jeanne in an atomic transaction...");
var johnSpec = new UserCreationSpec("John", "*****@*****.**");
var jeanneSpec = new UserCreationSpec("Jeanne", "*****@*****.**");
userCreationService.CreateListOfUsers(johnSpec, jeanneSpec);
Console.WriteLine("Done.\n");
Console.WriteLine("Trying to retrieve our newly created users from the data store...");
var createdUsers = userQueryService.GetUsers(johnSpec.Id, jeanneSpec.Id);
Console.WriteLine("OK. Found {0} persisted users.", createdUsers.Count());
Console.WriteLine("Press enter to continue...");
Console.ReadLine();
//-- Demo of nested SessionScopes in the face of an exception.
// If any of the provided users failed to get persisted, none should get persisted.
Console.WriteLine("Creating 2 new users called Julie and Marc in an atomic transaction. Will make the persistence of the second user fail intentionally in order to test the atomicity of the transaction...");
var julieSpec = new UserCreationSpec("Julie", "*****@*****.**");
var marcSpec = new UserCreationSpec("Marc", "*****@*****.**");
try
{
userCreationService.CreateListOfUsersWithIntentionalFailure(julieSpec, marcSpec);
Console.WriteLine("Done.\n");
}
catch (Exception e)
{
Console.WriteLine(e.Message);
Console.WriteLine();
}
Console.WriteLine("Trying to retrieve our newly created users from the data store...");
var maybeCreatedUsers = userQueryService.GetUsers(julieSpec.Id, marcSpec.Id);
Console.WriteLine("Found {0} persisted users. If this number is 0, we're all good. If this number is not 0, we have a big problem.", maybeCreatedUsers.Count());
Console.WriteLine("Press enter to continue...");
Console.ReadLine();
//-- Demo of explicit database transaction isolation level.
Console.WriteLine("Trying to retrieve user John within a READ UNCOMMITTED database transaction...");
// You'll want to use SQL Profiler or Entity Framework Profiler to verify that the correct transaction isolation
// level is being used.
var userMaybeUncommitted = userQueryService.GetUserUncommitted(johnSpec.Id);
Console.WriteLine("OK. User found: {0}", userMaybeUncommitted);
Console.WriteLine("Press enter to continue...");
Console.ReadLine();
//-- Demonstration of SessionScope and parallel programming
Console.WriteLine("Calculating and storing the credit score of all users in the database in parallel...");
userCreditScoreService.UpdateCreditScoreForAllUsers();
Console.WriteLine("Done.");
}
catch (Exception e)
{
Console.WriteLine(e);
}
Console.WriteLine();
Console.WriteLine("The end.");
Console.WriteLine("Press enter to exit...");
Console.ReadLine();
}
static void Main(string[] args)
{
// Wire up unity
var container = new UnityContainer();
// Register all types where Interface and Class name match. i.e. ISomething, Something
container.RegisterTypes(AllClasses.FromLoadedAssemblies(), WithMappings.FromMatchingInterface, WithName.Default);
// Register where names don't match
container.RegisterType<IAmbientDbLocator, EntityFrameworkAmbientLocator>();
container.RegisterType<IDbScopeFactory, EntityFrameworkScopeFactory>();
// Resolve required interfaces
var dbScopeFactory = container.Resolve<IDbScopeFactory>();
var userCreationService = container.Resolve<IUserCreationService>();
var userQueryService = container.Resolve<IUserQueryService>();
var userEmailService = container.Resolve<IUserEmailService>();
var userCreditScoreService = container.Resolve<IUserCreditScoreService>();
try
{
Console.WriteLine("This demo application will create a database named DbContextScopeDemo in the default SQL Server instance on localhost. Edit the connection string in UserManagementDbContext if you'd like to create it somewhere else.");
Console.WriteLine("Press enter to start...");
Console.ReadLine();
//-- Demo of typical usage for read and writes
Console.WriteLine("Creating a user called Mary...");
var marysSpec = new UserCreationSpec("Mary", "*****@*****.**");
userCreationService.CreateUser(marysSpec);
Console.WriteLine("Done.\n");
Console.WriteLine("Trying to retrieve our newly created user from the data store...");
var mary = userQueryService.GetUser(marysSpec.Id);
Console.WriteLine("OK. Persisted user: {0}", mary);
Console.WriteLine("Press enter to continue...");
Console.ReadLine();
//-- Demo of nested DbScopes
Console.WriteLine("Creating 2 new users called John and Jeanne in an atomic transaction...");
var johnSpec = new UserCreationSpec("John", "*****@*****.**");
var jeanneSpec = new UserCreationSpec("Jeanne", "*****@*****.**");
userCreationService.CreateListOfUsers(johnSpec, jeanneSpec);
Console.WriteLine("Done.\n");
Console.WriteLine("Trying to retrieve our newly created users from the data store...");
var createdUsers = userQueryService.GetUsers(johnSpec.Id, jeanneSpec.Id);
Console.WriteLine("OK. Found {0} persisted users.", createdUsers.Count());
Console.WriteLine("Press enter to continue...");
Console.ReadLine();
//-- Demo of nested DbScopes in the face of an exception.
// If any of the provided users failed to get persisted, none should get persisted.
Console.WriteLine("Creating 2 new users called Julie and Marc in an atomic transaction. Will make the persistence of the second user fail intentionally in order to test the atomicity of the transaction...");
var julieSpec = new UserCreationSpec("Julie", "*****@*****.**");
var marcSpec = new UserCreationSpec("Marc", "*****@*****.**");
try
{
userCreationService.CreateListOfUsersWithIntentionalFailure(julieSpec, marcSpec);
Console.WriteLine("Done.\n");
}
catch (Exception e)
{
Console.WriteLine(e.Message);
Console.WriteLine();
}
Console.WriteLine("Trying to retrieve our newly created users from the data store...");
var maybeCreatedUsers = userQueryService.GetUsers(julieSpec.Id, marcSpec.Id);
Console.WriteLine("Found {0} persisted users. If this number is 0, we're all good. If this number is not 0, we have a big problem.", maybeCreatedUsers.Count());
Console.WriteLine("Press enter to continue...");
Console.ReadLine();
//-- Demo of DbScope within an async flow
Console.WriteLine("Trying to retrieve two users John and Jeanne sequentially in an asynchronous manner...");
// We're going to block on the async task here as we don't have a choice. No risk of deadlocking in any case as console apps
// don't have a synchronization context.
var usersFoundAsync = userQueryService.GetTwoUsersAsync(johnSpec.Id, jeanneSpec.Id).Result;
Console.WriteLine("OK. Found {0} persisted users.", usersFoundAsync.Count());
Console.WriteLine("Press enter to continue...");
Console.ReadLine();
//-- Demo of explicit database transaction.
Console.WriteLine("Trying to retrieve user John within a READ UNCOMMITTED database transaction...");
// You'll want to use SQL Profiler or Entity Framework Profiler to verify that the correct transaction isolation
// level is being used.
var userMaybeUncommitted = userQueryService.GetUserUncommitted(johnSpec.Id);
Console.WriteLine("OK. User found: {0}", userMaybeUncommitted);
Console.WriteLine("Press enter to continue...");
Console.ReadLine();
//-- Demo of disabling the DbScope nesting behaviour in order to force the persistence of changes made to entities
// This is a pretty advanced feature that you can safely ignore until you actually need it.
Console.WriteLine("Will simulate sending a Welcome email to John...");
using (var parentScope = dbScopeFactory.Create())
{
var parentDbContext = parentScope.Get<UserManagementDbContext>();
// Load John in the parent DbContext
var john = parentDbContext.Users.Find(johnSpec.Id);
Console.WriteLine("Before calling SendWelcomeEmail(), john.WelcomeEmailSent = " + john.WelcomeEmailSent);
// Now call our SendWelcomeEmail() business logic service method, which will
// update John in a non-nested child context
userEmailService.SendWelcomeEmail(johnSpec.Id);
// Verify that we can see the modifications made to John by the SendWelcomeEmail() method
Console.WriteLine("After calling SendWelcomeEmail(), john.WelcomeEmailSent = " + john.WelcomeEmailSent);
// Note that even though we're not calling SaveChanges() in the parent scope here, the changes
// made to John by SendWelcomeEmail() will remain persisted in the database as SendWelcomeEmail()
// forced the creation of a new DbScope.
}
Console.WriteLine("Press enter to continue...");
Console.ReadLine();
//-- Demonstration of DbScope and parallel programming
Console.WriteLine("Calculating and storing the credit score of all users in the database in parallel...");
userCreditScoreService.UpdateCreditScoreForAllUsers();
Console.WriteLine("Done.");
}
catch (Exception e)
{
Console.WriteLine(e);
}
Console.WriteLine();
Console.WriteLine("The end.");
Console.WriteLine("Press enter to exit...");
Console.ReadLine();
}
static void Main(string[] args)
{
//-- Poor-man DI - build our dependencies by hand for this demo
//var dbcontextFactory = new UserManagementDbContextFactory("data source=192.168.0.11;initial catalog=DbContextScopeDemo1;persist security info=True;user id=test;password=111111;MultipleActiveResultSets=True;App=EntityFramework");
var dbcontextFactory = new DbContextFactory("server=127.0.0.1;port=3306;AutoEnlist=true;user id=root;password=jooge2012;persistsecurityinfo=True;database=test;oldguids=True");
var dbContextScopeFactory = new DbContextScopeFactory(dbcontextFactory);
var ambientDbContextLocator = new AmbientDbContextLocator();
var userRepository = new UserRepository(ambientDbContextLocator);
var userCreationService = new UserCreationService(dbContextScopeFactory, userRepository);
var userQueryService = new UserQueryService(dbContextScopeFactory, userRepository);
var userEmailService = new UserEmailService(dbContextScopeFactory);
var userCreditScoreService = new UserCreditScoreService(dbContextScopeFactory);
var userClassService = new UserClassService(dbContextScopeFactory);
try
{
Console.WriteLine("This demo application will create a database named DbContextScopeDemo in the default SQL Server instance on localhost. Edit the connection string in UserManagementDbContext if you'd like to create it somewhere else.");
Console.WriteLine("Press enter to start...");
Console.ReadLine();
Console.WriteLine("一个dbScope中使用2个DbContext 创建 a user and userClass Terry+English...");
var user = new User
{
Id = Guid.NewGuid(),
Name = "Terry",
Email = "*****@*****.**",
WelcomeEmailSent = false,
CreatedOn = DateTime.UtcNow
};
using (var dbContextScope = dbContextScopeFactory.Create())
{
dbContextScope.DbContexts.Get <UserManagementDbContext>().Users.Add(user);
userClassService.CreateUserClass(user.Name, "English");
dbContextScope.SaveChanges();
}
Console.WriteLine("检查数据库应该有相应的记录user表 和 userClass表");
Console.WriteLine("Press enter to continue...");
Console.ReadLine();
Console.WriteLine("2个dbcontext 使用事务的情况，");
Console.WriteLine("Press enter to continue...");
Console.ReadLine();
user = new User
{
Id = Guid.NewGuid(),
Name = "Mark",
Email = "*****@*****.**",
WelcomeEmailSent = false,
CreatedOn = DateTime.UtcNow
};
int rowCount = 0;
try
{
using (var s = new TransactionScope())
{
using (var dbContextScope = dbContextScopeFactory.Create())
{
dbContextScope.DbContexts.Get <UserManagementDbContext>().Users.Add(user);
dbContextScope.SaveChanges();
}
rowCount = userClassService.GetRowCount();
userClassService.CreateUserClass(user.Name, "English");
throw new Exception("模拟错误");
s.Complete();
}
}
catch
{
}
var tempUsers = userQueryService.GetUsers(user.Id);
Console.WriteLine("Found {0} persisted users. If this number is 0, we're all good. If this number is not 0, we have a big problem.", tempUsers.Count());
if (rowCount == userClassService.GetRowCount())
{
Console.WriteLine("userClass表的数量没有变化，是正确的，如果变化了就不对了");
}
else
{
Console.WriteLine("userClass表的数量变化了，是不对的。");
}
//-- Demo of typical usage for read and writes
Console.WriteLine("Creating a user called Mary...");
var marysSpec = new UserCreationSpec("Mary", "*****@*****.**");
userCreationService.CreateUser(marysSpec);
Console.WriteLine("Done.\n");
Console.WriteLine("Trying to retrieve our newly created user from the data store...");
var mary = userQueryService.GetUser(marysSpec.Id);
Console.WriteLine("OK. Persisted user: {0}", mary);
Console.WriteLine("Press enter to continue...");
Console.ReadLine();
//-- Demo of nested DbContextScopes
Console.WriteLine("Creating 2 new users called John and Jeanne in an atomic transaction...");
var johnSpec = new UserCreationSpec("John", "*****@*****.**");
var jeanneSpec = new UserCreationSpec("Jeanne", "*****@*****.**");
userCreationService.CreateListOfUsers(johnSpec, jeanneSpec);
Console.WriteLine("Done.\n");
Console.WriteLine("Trying to retrieve our newly created users from the data store...");
var createdUsers = userQueryService.GetUsers(johnSpec.Id, jeanneSpec.Id);
Console.WriteLine("OK. Found {0} persisted users.", createdUsers.Count());
Console.WriteLine("Press enter to continue...");
Console.ReadLine();
//-- Demo of nested DbContextScopes in the face of an exception.
// If any of the provided users failed to get persisted, none should get persisted.
Console.WriteLine("Creating 2 new users called Julie and Marc in an atomic transaction. Will make the persistence of the second user fail intentionally in order to test the atomicity of the transaction...");
var julieSpec = new UserCreationSpec("Julie", "*****@*****.**");
var marcSpec = new UserCreationSpec("Marc", "*****@*****.**");
try
{
userCreationService.CreateListOfUsersWithIntentionalFailure(julieSpec, marcSpec);
Console.WriteLine("Done.\n");
}
catch (Exception e)
{
Console.WriteLine(e.Message);
Console.WriteLine();
}
Console.WriteLine("Trying to retrieve our newly created users from the data store...");
var maybeCreatedUsers = userQueryService.GetUsers(julieSpec.Id, marcSpec.Id);
Console.WriteLine("Found {0} persisted users. If this number is 0, we're all good. If this number is not 0, we have a big problem.", maybeCreatedUsers.Count());
Console.WriteLine("Press enter to continue...");
Console.ReadLine();
//-- Demo of DbContextScope within an async flow
Console.WriteLine("Trying to retrieve two users John and Jeanne sequentially in an asynchronous manner...");
// We're going to block on the async task here as we don't have a choice. No risk of deadlocking in any case as console apps
// don't have a synchronization context.
var usersFoundAsync = userQueryService.GetTwoUsersAsync(johnSpec.Id, jeanneSpec.Id).Result;
Console.WriteLine("OK. Found {0} persisted users.", usersFoundAsync.Count());
Console.WriteLine("Press enter to continue...");
Console.ReadLine();
//-- Demo of explicit database transaction.
Console.WriteLine("Trying to retrieve user John within a READ UNCOMMITTED database transaction...");
// You'll want to use SQL Profiler or Entity Framework Profiler to verify that the correct transaction isolation
// level is being used.
var userMaybeUncommitted = userQueryService.GetUserUncommitted(johnSpec.Id);
Console.WriteLine("OK. User found: {0}", userMaybeUncommitted);
Console.WriteLine("Press enter to continue...");
Console.ReadLine();
//-- Demo of disabling the DbContextScope nesting behaviour in order to force the persistence of changes made to entities
// This is a pretty advanced feature that you can safely ignore until you actually need it.
Console.WriteLine("Will simulate sending a Welcome email to John...");
using (var parentScope = dbContextScopeFactory.Create())
{
var parentDbContext = parentScope.DbContexts.Get <UserManagementDbContext>();
// Load John in the parent DbContext
var john = parentDbContext.Users.Find(johnSpec.Id);
Console.WriteLine("Before calling SendWelcomeEmail(), john.WelcomeEmailSent = " + john.WelcomeEmailSent);
// Now call our SendWelcomeEmail() business logic service method, which will
// update John in a non-nested child context
userEmailService.SendWelcomeEmail(johnSpec.Id);
// Verify that we can see the modifications made to John by the SendWelcomeEmail() method
Console.WriteLine("After calling SendWelcomeEmail(), john.WelcomeEmailSent = " + john.WelcomeEmailSent);
// Note that even though we're not calling SaveChanges() in the parent scope here, the changes
// made to John by SendWelcomeEmail() will remain persisted in the database as SendWelcomeEmail()
// forced the creation of a new DbContextScope.
}
Console.WriteLine("Press enter to continue...");
Console.ReadLine();
//-- Demonstration of DbContextScope and parallel programming
Console.WriteLine("Calculating and storing the credit score of all users in the database in parallel...");
userCreditScoreService.UpdateCreditScoreForAllUsers();
Console.WriteLine("Done.");
Console.WriteLine("Trying to retrieve users by where clause.");
var users = userQueryService.GetUserByWhereClause(" WelcomeEmailSent = 1 ");
Console.WriteLine("OK. WelcomeEmailSent user count: {0}", users.Count());
Console.WriteLine("Press enter to continue...");
Console.ReadLine();
}
catch (Exception e)
{
Console.WriteLine(e);
}
Console.WriteLine();
Console.WriteLine("The end.");
Console.WriteLine("Press enter to exit...");
Console.ReadLine();
}
