How to choose to use IEnumerable, ICollection, IList

IEnumerable, ICollection, IList, each interface is only suitable for some specific scenarios, how to use it differently?

The IEnumerable interface only provides a way to get iterators, which is why you can use a foreach traversal to implement the IEnumerable interface Collection.

public interface IEnumerable

{

    IEnumerator GetEnumerator ();

}

The ICollection implements the IEnumerable interface, so that in addition to the ability to have IEnumerable interfaces, other capabilities are included.

public interface Icollection:ienumerable

{

    int count{get;}

    BOOL Issynchronized{get;}

    Object Syncroot{get;}

    IEnumerator GetEnumerator ();

    void CopyTo (array array, int index);

}

IList implements both the ICollection and IEnumerable interfaces, which, on the basis of 2 interfaces, can add, remove, or empty the collection, and also provide access to the collection elements based on the index.

Public interface Ilist:icollection, IEnumerable

{

    BOOL Isfixedsize{get;}

    BOOL Isreadonly{get;}

    Object This[int index] {get;set;}

    int Add (Object value);

    void Clear ();

    BOOL Contains (Object value);

    int IndexOf (Object value);

    void Insert (int index, Object value);

    void Remove (Object value);

    void RemoveAt (int index);

}

Summarize:

If you only want to traverse the collection, use IEnumerable, ienumerable<t>
If you want to traverse, modify the collection, and the navigation properties that require lazy loading, use ICollection, icollection<t>
If you want to traverse, modify, add, empty, use an index, use IList, ilist<t>

How to choose to use IEnumerable, ICollection, IList