C# List vs IEnumerable performance question

Question

Hi suppose these 2 methods:

private List GetProviderForType(Type type)
        {
            List returnValue = new         


        

Answer 1

The Main Difference Between IEnumerable and IList:

IEnumerable: Implements MoveNext,Reset,Get Current Methods and Returns a Type of IEnumerator to Iterate Through Records.

IList : Exposes the IEnumerable Interface as well as it is also a collection of non-generic objects which can accessed through index so IEnumerable+ICollection(Manipulation of data) and add,remove,Insert(at specific Index) are the useful methods implemented by IList.

After looking at your Code In My Opinion IEnumerable is more efficient but returning list is also useful if you want to do some manipulation with data and if you just want to Iterate through data then IEnumerable is preferable.