Cast IList to List

Question

I am trying to cast IList type to List type but I am getting error every time.

List<SubProduct> subProducts= Model.subproduct;

Model.subproduct returns IList<SubProduct>.

Answer 1

Try

List<SubProduct> subProducts = new List<SubProduct>(Model.subproduct);

or

List<SubProduct> subProducts = Model.subproducts as List<SubProduct>;

Answer 2

How about this:

List<SubProduct> subProducts = Model.subproduct.ToList();

Answer 3

In my case I had to do this, because none of the suggested solutions were available:

List<SubProduct> subProducts = Model.subproduct.Cast<SubProduct>().ToList();

Answer 4

List<SubProduct> subProducts= (List<SubProduct>)Model.subproduct;

The implicit conversion failes because List<> implements IList, not viceversa. So you can say IList<T> foo = new List<T>(), but not List<T> foo = (some IList-returning method or property).

Answer 5

List<ProjectResources> list = new List<ProjectResources>();        
IList<ProjectResources> obj = `Your Data Will Be Here`;
list = obj.ToList<ProjectResources>();

This Would Convert IList Object to List Object.

Answer 6

The other answers all recommend to use AddRange with an IList.

A more elegant solution that avoids the casting is to implement an extension to IList to do the job.

In VB.NET:

<Extension()>
Public Sub AddRange(Of T)(ByRef Exttype As IList(Of T), ElementsToAdd As IEnumerable(Of T))
   For Each ele In ElementsToAdd
      Exttype.Add(ele)
   Next
End Sub

And in C#:

public void AddRange<T>(this ref IList<T> Exttype, IEnumerable<T> ElementsToAdd)
{
    foreach (var ele in ElementsToAdd)
    {
        Exttype.Add(ele);
    }
}

Answer 7

This is the best option to cast/convert list of generic object to list of string.

object valueList;
List<string> list = ((IList)valueList).Cast<object>().Select(o => o.ToString()).ToList();