public async void LazyLoadCollection()
{
IEnumerable <LazyObject> paramObjs = Faker.RandomCollection(LazyObject.Random);
// Setup DB & LazyLoader
SQLiteConnectionAsync db = new SQLiteConnectionAsync(new LazyObjectDb());
DbLazyLoad <LazyObject> lazyLoader =
await DbLazyLoad <LazyObject> .GetOrCreateInstanceAsync(db).ConfigureAwait(true);
await db.InsertAllAsync(paramObjs).ConfigureAwait(true);
// Test shallow loading
// ToList() is necessary, as db.Table<T> return a custom Enumerable
// implementation which apparently doesn't allow for true references
IEnumerable <LazyObject> fetchedObjs =
await db.Table <LazyObject>().ShallowLoad(lazyLoader).ToListAsync().ConfigureAwait(true);
fetchedObjs.Should().OnlyContain(lo => lo.Value == null && lo.Id > 0);
fetchedObjs.ShouldAllBeEquivalentTo(
paramObjs,
config =>
config.Including(ctx => ctx.SelectedMemberPath.EndsWith(".Id"))
.Including(ctx => ctx.SelectedMemberPath.EndsWith(".Idx")));
// Test further loading
IEnumerable <LazyObject> furtherObjs =
await db.Table <LazyObject>().FurtherLoad(lazyLoader).ToListAsync().ConfigureAwait(true);
furtherObjs.Should().OnlyContain(lo => lo.Value != null);
lazyLoader.UpdateFromFurtherLoad(fetchedObjs, furtherObjs, lo => lo.Id);
fetchedObjs.ShouldAllBeEquivalentTo(
furtherObjs,
config => config.Including(ctx => ctx.SelectedMemberPath.EndsWith(".Value")));
fetchedObjs.ShouldAllBeEquivalentTo(
paramObjs,
config =>
config.Including(ctx => ctx.SelectedMemberPath.EndsWith(".Id"))
.Including(ctx => ctx.SelectedMemberPath.EndsWith(".Idx")));
// Test further unloading
foreach (LazyObject fetchedObj in fetchedObjs)
{
lazyLoader.LazyUnload(fetchedObj);
}
fetchedObjs.Should().OnlyContain(lo => lo.Value == null && lo.Id > 0);
}
/// <summary>
/// Initializes a new instance of the <see cref="AsyncDbListBase{T}" /> class.
/// </summary>
/// <param name="db">Database instance</param>
/// <param name="lazyLoad">Whether to use lazy loading</param>
protected AsyncDbListBase(IDatabaseAsync db, bool lazyLoad = false)
{
Status = ReviewStatus.New;
LockObject = new object();
LoadCompletionSource = null;
Db = db;
if (lazyLoad)
{
LazyLoader = DbLazyLoad <T> .GetOrCreateInstanceAsync(db).Result;
}
_index = -1;
_current = null;
Objects = null;
}