System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator()
{
System.Collections.IEnumerator rator = null;
switch (flags)
{
case EnumerationFlags.Forward:
rator = new Enumerator(this);
break;
case EnumerationFlags.Reverse:
rator = new ReverseEnumerator(this);
break;
case EnumerationFlags.ForwardPosition:
rator = new PostionEnumerator(this);
break;
case EnumerationFlags.ReversePosition:
rator = new ReversePostionEnumerator(this);
break;
default:
rator = new Enumerator(this);
break;
}
flags = 0;
return(rator);
}
public void InsertItemsAtIndex()
{
AddToEmpty(10);
// Insert 10 items at the front of the list
for (int i = 20; i >= 11; i--)
{
testList.Insert(0, i);
}
Assert.AreEqual(20, testList.Count);
// Verify the first 10 items are the inserted items
int iTest = 11;
IEnumerator enumerator = testList.GetEnumerator();
while (iTest <= 20)
{
enumerator.MoveNext();
int iList = (int)enumerator.Current;
Assert.AreEqual(iTest, iList);
iTest++;
}
// Verify that the last 10 items are the ones that were added originally
iTest = 10;
enumerator = new ReverseEnumerator <int>(testList);
while (iTest >= 1)
{
enumerator.MoveNext();
int iList = (int)enumerator.Current;
Assert.AreEqual(iTest, iList);
iTest--;
}
}
public IEnumerable <T> Reverse()
{
ReverseEnumerator e = new ReverseEnumerator(this);
while (e.MoveNext())
{
yield return(e.Current);
}
}
/// <summary>
/// Returns an enumerator for the list
/// </summary>
/// <returns>the enumerator</returns>
public virtual IEnumerator <T> GetEnumerator()
{
IEnumerator <T> rator = null;
switch (flags)
{
case EnumerationFlags.Forward:
rator = new Enumerator(this);
break;
case EnumerationFlags.Reverse:
rator = new ReverseEnumerator(this);
break;
default:
rator = new Enumerator(this);
break;
}
flags = 0;
return(rator);
}
public void ReverseEnumeratorTest()
{
Assert.IsTrue(testList.Empty);
AddToEmpty(10);
int i = 10;
var reverse = new ReverseEnumerator <int>(testList);
while (reverse.MoveNext())
{
Assert.AreEqual(i, reverse.Current);
i--;
}
while (reverse.MovePrevious())
{
i++;
Assert.AreEqual(i, reverse.Current);
}
Assert.AreEqual(10, i); // Ran through all the scenarios
}
public void AddItems()
{
AddToEmpty(10);
// Verify the Forward Iterator
int iTest = 1;
foreach (int iList in testList)
{
Assert.AreEqual(iList, iTest);
iTest++;
}
// Verify the Reverse Iterator
iTest = 10;
IEnumerator enumerator = new ReverseEnumerator <int>(testList);
while (enumerator.MoveNext())
{
int iList = (int)enumerator.Current;
Assert.AreEqual(iTest, iList);
iTest--;
}
}
