Can not delete an elment from the array via lists C#

Question

This method doesn't work at all:

    public static void Delete(ref Prot[] pack, Prot prot)
    {
        var temp = new List<Prot>(pack);
        temp.Remove(prot);
        pack = temp.ToArray();
    }

What am I doing wrong?

Thank you.

Answer 1

Your class Prot needs to override the Object.Equals() method. This is how List<T>.Remove works. From the documentation:

If type T implements the IEquatable<T> generic interface, the equality comparer is the Equals method of that interface; otherwise, the default equality comparer is Object.Equals.

If you don't override Object.Equals it will just use the default implementation which checks for reference equality, not value equality.

So, temp.Remove(prot); was never removing any values. (This can be validated based on the return value of Remove. It returns true if it successfully removes a value, and false otherwise.

Here's a basic example: http://ideone.com/vOZoYI

---

Initial Answer (issue was a typo in question).

You are modifying a new object, a List<Prot>, not the Prot[] parameter. If you assign pack to the List<Prot>.ToArray() then it will remove it from the array passed in.

public static void Delete(ref Prot[] pack, Prot prot)
{
    var temp = new List<Prot>(pack);
    temp.Remove(prot);
    pack = temp.ToArray();
}