ArgumentNullExeption in an array that i cant for the life of me figure out :'(
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I have been up half the night and still trying to get this null exeption figured out. I have read a few of texts about this issue but none has helped me in any way, to me what the probem is as it should work :/  It just chrashes at this peice of code:


            Private void UpdateGUI()
            {
            string selectedItem  = cmbDisplayOptions.Items[cmbDisplayOptions.SelectedIndex].ToString();
            rdbtReserv.Checked = true;            
            lstReservations.Items.Clear();           
            lstReservations.Items.AddRange(m_seatMngr.GetSeatInfoStrings(selectedItem));
            }

lstReservations.Items.AddRange(m_seatMngr.GetSeatInfoStrings(selectedItem)); Gives me the ArgumentNullExeption, but to me it should not do that.

the addrange sends string selectedItem to another class:

        public string[] GetSeatInfoStrings(string selectedItem)
        {
            int count = GetNumOfSeats(selectedItem);

            if (count <= 0)
            {
                return null;
            }

            string[] strSeatInfoStrings = new string[count];
                       
            for (int index = 0; index <= m_totNumOfSeats - 1; index++)
            {
                strSeatInfoStrings[index] = GetSeatInfoAt(index); 
            }

            return strSeatInfoStrings;

        }

This int count = GetNumOfSeats(selectedItem); goes to here and returns with an int:

        private int GetNumOfSeats(string selectedItem)
        {
            if (selectedItem == "ReservedSeats")
            {
                return GetNumReserved();
            }
            if (selectedItem == "VacantSeats")
            {
                return GetNumVacant();
            }
            else
            {
                return m_totNumOfSeats;
            }
        }

I have checked the arrayed have the correct number of spaces(60) and that selectedItem has a string(Allseats to start with so it should return m_totnumOfSeats wich is an int of 60) But then in the private int GetNumOfSeats something goes wrong and it returns null and...well why? I cant see the problem..maybe gone blind by trying to find the issue. Always got outstanding help here and i have learned tons!! So maybe someone can point out all the issues there is in my code. 

Thanks a million in advance for any and all advice! 

//Regards
    