How do I cast a List effectively?

Question

I have a

List 

but I need a

List  

Is there a way to cast this in c

Answer 1

Since the list is coming from

List<InputField> list = (from i .... select i).ToList();

Couldn't you just fix the "select i" part to instead return IDataField instead? Something like this:

List<InputField> list = (from i .... select (IDataField)i).ToList();

If that doesn't work, perhaps the "Cast" extension to IEnumerable will work:

List<DataField> list2 = list.Cast<IDataField>();

Answer 2

I have the following string

 var str = "2 4 7 8 10";

when I cast as follow

var numbersInt2 = numbers.Split(' ')
                .ToList().Cast<int>().ToList();

it returns an exception but

System.InvalidCastException: 'Specified cast is not valid.'

, if using the following

var numbersInt = numbers.Split(' ')
                .ToList().ConvertAll(int.Parse);

it works.