DiscountItemCollectionEnumerator Class

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An enumerator over the DiscountItemCollection class. This class cannot be inherited.

Namespace: Microsoft.CommerceServer.Runtime.Marketing
Assembly: Microsoft.CommerceServer.Runtime (in Microsoft.CommerceServer.Runtime.dll)


Public NotInheritable Class DiscountItemCollectionEnumerator _
    Implements IEnumerator(Of DiscountItem), IDisposable,  _
Dim instance As DiscountItemCollectionEnumerator
public sealed class DiscountItemCollectionEnumerator : IEnumerator<DiscountItem>, 
    IDisposable, IEnumerator
public ref class DiscountItemCollectionEnumerator sealed : IEnumerator<DiscountItem^>, 
    IDisposable, IEnumerator
public final class DiscountItemCollectionEnumerator implements IEnumerator<DiscountItem>, IDisposable, IEnumerator


Supports iteration over the DiscountItemCollection. This class cannot be inherited.

Initially, the enumerator is positioned before the first element in the collection. Reset()()() also brings the enumerator back to this position. At this position, calling Current throws an exception. Therefore, you must call MoveNext()()() to advance the enumerator to the first element of the collection before reading the value of Current()()()

Current returns the same object until either MoveNext or Reset is called. MoveNext sets Current to the next element.

After the end of the collection is passed, the enumerator is positioned after the last element in the collection, and calling MoveNext returns false. If the last call to MoveNext returned false, calling Current throws an exception. To set Current to the first element of the collection again, you can call Reset followed by MoveNext.

An enumerator remains valid as long as the collection remains unchanged. If changes are made to the collection, such as adding, modifying, or deleting elements, the enumerator is irrecoverably invalidated and the next call to MoveNext or Reset throws an InvalidOperationException. If the collection is modified between MoveNext and Current, Current will return the element that it is set to, even if the enumerator is already invalidated.

The enumerator does not have exclusive access to the collection; therefore, enumerating through a collection is not a thread-safe procedure. Even when a collection is synchronized, other threads could still modify the collection, which causes the enumerator to throw an exception. To guarantee thread safety during enumeration, you can lock the collection during the entire enumeration or catch the exceptions that result from changes made by other threads.

Inheritance Hierarchy


Thread Safety

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

See Also


DiscountItemCollectionEnumerator Members

Microsoft.CommerceServer.Runtime.Marketing Namespace