Always returns a new list from a function or not?

Question

I need to create a public function for a class where this function returns an Listelement, such as List (employee).

This function will be called often from outside this class.

In terms of memory consumption is better:

• always initialize a new list inside this function, add elements to it and return this list or;
• have a list stored in a field, clear its elements, add new elements and return this list

Code example:

1.

public List<employee> GetItems()
{
    List<employee> list = new List<employee>();
    list.Add(new employee());
    list.Add(new employee());
    ....
    return list;
}

2.

private List<employee> _list = new List<employee>();
public List<employee> GetItems()
{
    _list.Clear();
    _list.Add(new employee());
    _list.Add(new employee());
    ...
    return _list;
}

Is one of the above preferable in terms of memory consumption? And in what circumstances should one of the above be used instead of the other option?

Answer 1

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Answer 4

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public IEnumerable<employee> GetItems()
{
  return new List<employee> { 
    new employee("Alan"),
    new employee("Bob"),  
    new employee("Carla")
  }; 
}