System.CollectionsRepresents a type that is an iterable collection. This is the base interface for all generic and non-generic collection types in the .NET Framework.
Types that implement IEnumerable can be enumerated by a for-each loop (foreach in C#, For Each in Visual Basic). The IEnumerable interface exposes the GetEnumerator method, which returns an IEnumerator object. The IEnumerator object implements the basic enumeration capabilities, such as reading the next element and resetting the enumeration.
System.Collections.Generic.IEnumerable<T> interface.
GetEnumerator()IEnumerator GetEnumerator()
Returns an enumerator that iterates through a collection.
// Assume 'myCollection' is an object that implements IEnumerable
IEnumerable myCollection = /* ... your collection ... */;
IEnumerator enumerator = myCollection.GetEnumerator();
try
{
while (enumerator.MoveNext())
{
object currentItem = enumerator.Current;
// Process currentItem
Console.WriteLine(currentItem);
}
}
finally
{
// It's important to dispose the enumerator if it implements IDisposable
if (enumerator is IDisposable disposableEnumerator)
{
disposableEnumerator.Dispose();
}
}
The IEnumerable interface is the fundamental interface for enabling collection iteration. It is the base interface for the IEnumerable<T> generic interface.
When you use a for-each loop in C#, the compiler translates the loop into code that uses the IEnumerable and IEnumerator interfaces.
A collection must implement IEnumerable to be enumerated by the for-each loop. This interface allows you to iterate over the elements of a collection without exposing its underlying representation.