public void removeWhere_numElements(int numElementsToRemove)
{
var collection = new MyObservableCollection <int>();
List <int> removedItems = new List <int>();
collection.ItemDetached += (sender, oldItem, index) =>
{
removedItems.Add(oldItem);
};
int maxCount = 30;
collection.AddRange(Enumerable.Range(0, maxCount));
int initCount = collection.Count;
int multiple = 3;
collection.RemoveWhere(val =>
{
int remainder;
int div = Math.DivRem(val, multiple, out remainder);
return(remainder == 0);
}, numElementsToRemove);
Assert.IsTrue(collection.Count == initCount - numElementsToRemove);
var xRemovedItems = Enumerable.Range(0, numElementsToRemove)
.Select(val => val * multiple)
.ToArray();
Assert.AreEqual(removedItems.Count, xRemovedItems.Length);
Assert.IsTrue(!removedItems.Except(xRemovedItems).Any());
Assert.IsTrue(!xRemovedItems.Except(removedItems).Any());
Enumerable.Range(0, maxCount)
.Except(xRemovedItems)
.ForEach(val => Assert.IsTrue(collection.Contains(val)));
xRemovedItems.ForEach(val => Assert.IsFalse(collection.Contains(val)));
}
public void AddRangeTest2()
{
var collection = new MyObservableCollection <int>();
Enumerable.Range(10, 15).ForEach(val => collection.Add(val));
int initCount = collection.Count;
int attachedCount = 0;
collection.ItemAttached += (sender, newItem, index) =>
{
Assert.IsTrue(ReferenceEquals(sender, collection));
attachedCount++;
};
int addedCount = 0;
collection.ItemAdded += (sender, newItem, index) =>
{
Assert.IsTrue(ReferenceEquals(sender, collection));
addedCount++;
};
var newItems = Enumerable.Range(0, 5).ToArray();
collection.AddRange(newItems);
Assert.AreEqual(attachedCount, newItems.Length);
Assert.AreEqual(addedCount, newItems.Length);
Assert.AreEqual(newItems.Length, collection.Count - initCount);
foreach (var item in newItems)
{
Assert.IsTrue(collection.Contains(item));
}
}
public void AddRangeTest()
{
var collection = new MyObservableCollection <int>();
int attachedCount = 0;
collection.ItemAttached += (sender, newItem, index) =>
{
Assert.IsTrue(ReferenceEquals(sender, collection));
attachedCount++;
};
int addedCount = 0;
collection.ItemAdded += (sender, newItem, index) =>
{
Assert.IsTrue(ReferenceEquals(sender, collection));
addedCount++;
};
var newItems = Enumerable.Range(0, 5).ToArray();
collection.AddRange(newItems);
Assert.AreEqual(attachedCount, newItems.Length);
Assert.AreEqual(addedCount, newItems.Length);
Assert.AreEqual(newItems.Length, collection.Count);
foreach (var item in newItems)
{
Assert.IsTrue(collection.Contains(item));
}
bool exceptionThrow = false;
try
{
collection.AddRange(null);
}
catch (Exception)
{
exceptionThrow = true;
}
Assert.IsFalse(exceptionThrow);
}