public void VoorbeeldVanConcurrency_Client2Wint()
{
using (var ctx1 = new SchoolContext())
using (var ctx2 = new SchoolContext())
{
ctx2.Database.Log = Console.WriteLine;
var p1 = ctx1.People.Find(14);
p1.FirstName = "Demo1";
var p2 = ctx2.People.Find(14);
p2.FirstName = "Demo2";
ctx1.SaveChanges();
try
{
ctx2.SaveChanges();
}
catch (DbUpdateConcurrencyException ex)
{
var entry = ex.Entries.First();
entry.OriginalValues.SetValues(entry.GetDatabaseValues());
ctx2.SaveChanges();
}
}
using (var ctx = new SchoolContext())
{
var p = ctx.People.Find(14);
Assert.AreEqual("Demo2", p.FirstName);
}
}
public void VoorbeeldVanMigration()
{
using (var context = new SchoolContext())
{
Assert.IsTrue(context.People.OfType<Student>().Any(s => s.FirstName == "Gytis"));
}
}
public static void ClassInit(TestContext tc)
{
Database.SetInitializer(new MigrateDatabaseToLatestVersion<SchoolContext, Configuration>());
using (var context = new SchoolContext())
{
context.Database.Initialize(true);
}
}
public void TestMethod1()
{
using (var context = new SchoolContext())
{
foreach (var p in context.People)
{
Console.WriteLine($"{p.FirstName} {p.LastName}");
}
}
}
public void VoorbeeldVanConcurrency()
{
using (var ctx1 = new SchoolContext())
using (var ctx2 = new SchoolContext())
{
var p1 = ctx1.People.Find(14);
p1.FirstName = "Demo1";
var p2 = ctx2.People.Find(14);
p2.FirstName = "Demo2";
ctx1.SaveChanges();
ctx2.SaveChanges();
}
}
public async Task TestVanAsyncMetTransactions()
{
var trans = new TransactionScope(TransactionScopeOption.RequiresNew,
TransactionScopeAsyncFlowOption.Enabled);
using (var context = new SchoolContext())
{
var p = context.People.Find(1);
p.FirstName = "TEST";
await context.SaveChangesAsync();
trans.Dispose();
using (new TransactionScope(TransactionScopeOption.RequiresNew))
using (var ctx2 = new SchoolContext())
{
var p2 = ctx2.People.Find(1);
Assert.AreNotEqual("TEST", p2.FirstName);
}
}
}
public void VoorbeeldVanConcurrency_Client2Verliest()
{
using (var ctx1 = new SchoolContext())
using (var ctx2 = new SchoolContext())
{
ctx2.Database.Log = Console.WriteLine;
var p1 = ctx1.People.Find(14);
p1.FirstName = "Demo1";
var p2 = ctx2.People.Find(14);
p2.FirstName = "Demo2";
var p3 = ctx2.People.Find(15);
p3.FirstName = "YetAnotherChange";
ctx1.SaveChanges();
try
{
ctx2.SaveChanges();
}
catch (DbUpdateConcurrencyException ex)
{
var entry = ex.Entries.First();
entry.Reload();
ctx2.SaveChanges();
}
}
using (var ctx = new SchoolContext())
{
var p2 = ctx.People.Find(14);
Assert.AreEqual("Demo1", p2.FirstName);
var p3 = ctx.People.Find(15);
Assert.AreEqual("YetAnotherChange", p3.FirstName);
}
}
