C# Console can't read google sheets data into list in program

Question

I am working on a console based search tool for "Warrants" in a game I play that searches off of a google sheet from the google sheets API and C#. Originally I made this on python and it worked perfectly but I had a lot of issues distributing my python file so I moved to C#.

The API is calling the data perfectly fine and I am able to present a list of all the data I was seeking on launch, but when I try and save it to list files inside my program I get the following: Unhandled exception. System.NullReferenceException: Object reference not set to an instance of an object.

I also added in a section that tells me the data type I am calling with row[1] and it says (only one "```", had to double to format): System.Collections.Generic.List``1[System.Object]

using Google.Apis.Auth.OAuth2;
using Google.Apis.Sheets.v4;
using Google.Apis.Sheets.v4.Data;
using Google.Apis.Services;
using Google.Apis.Util.Store;
using System;
using System.Collections.Generic;
using System.IO;
using System.Threading;
using System.Diagnostics;

namespace WarrantSearchProgram
{
    class Program
    {
        static readonly string[] Scopes = { SheetsService.Scope.SpreadsheetsReadonly };
        static readonly string ApplicationName = "WarrantSearchProgram";
        static readonly string SpreadsheetId = "SpreadsheetId";
        static readonly string sheet = "Imported Data";
        static SheetsService service;

        //List of Warrant Column Variables... Only nameList is being used for now
        public static IList<object> testOBJ;
        public static List<object> wtStatus;
        public static List<object> wtType;
        public static List<object> wtNum;
        public static IList<object> nameList;
        public static List<object> wtCivName;
        public static List<object> wtDOB;
        public static List<object> wtAddress;
        public static List<object> wtJs;
        public static List<object> wtCharges;
        public static List<object> wtEvidence;
        public static List<object> wtReqOfc;
        public static List<object> wtReqOfcNum;
        static void Main(string[] args)
        {
            //Set console color and other general settings
            Console.Title = "DOJ Warrant Search Program UNOFFICIAL";
            Console.BackgroundColor = ConsoleColor.Black;
            Console.ForegroundColor = ConsoleColor.Green;

            // Initialization of creds and google sheets
            GoogleCredential credential;

            using (var stream = new FileStream("credentials.json", FileMode.Open, FileAccess.Read))
            {
                credential = GoogleCredential.FromStream(stream)
                    .CreateScoped(Scopes);
            }

            // Create Google Sheets API service.
            service = new SheetsService(new BaseClientService.Initializer()
            {
                HttpClientInitializer = credential,
                ApplicationName = ApplicationName,
            });

            //First initilization of warrant sheet info, creates and manages variables.
            UpdateSheetData();

            while (true)
            {
                // Main repeating text and SEARCH INPUT
                Console.WriteLine("-----------------------------------------------");
                Console.WriteLine("Please type in a full name to search for warrants.");
                Console.WriteLine("Only ACTIVE warrants will be shown.");
                Console.WriteLine("Type in a warrant number to show extra info, including evidence, on just that warrant");
                Console.WriteLine("-----------------------------------------------");
                Console.Write("Search >>> ");
                string searchName = Console.ReadLine();
                searchName = searchName.ToUpper();
                Console.WriteLine();
                Console.Beep();
                Console.Clear();
            }

        }
        static void UpdateSheetData()
        {

        var range = $"{sheet}!A:F";
            SpreadsheetsResource.ValuesResource.GetRequest request =
                    service.Spreadsheets.Values.Get(SpreadsheetId, range);

            var response = request.Execute();
            IList<IList<object>> values = response.Values;

            if (values != null && values.Count > 0)
            {
                foreach (var row in values)
                {
                    // Calls the row (2nd, name) and displays each name in list
                    Console.WriteLine("{0}", row[1]);
                    Console.WriteLine(row.GetType().ToString());

                    // Attempts to build list of names in program ERROR HERE
                    nameList.Add(row[1]);

                }

            }
            else
            {
                Console.WriteLine("No data found.");
            }
        }
    }
}

I removed sections of the code that have nothing to do with this so its easier to read... As you can tell, I tried IList<object>, List<object>, and List<string> at different times and it didn't work for me.

My goal here is to load each column of data into a list that I can then perform searches on, index, and display matching data from other lists. This is all not very difficult to do once I can load the data up into the program and separate it. error at row 98

Answer 1

As per your comment, at line 98 you are trying to Add a value to the nameList, which may not be initialized. This is why you get the error you do, Object reference not set to an instance of an object. - The nameList wasn't initiated, so you can't call it's internal functions. You might want to instantiate it, anywhere before you call UpdateSheetData, e.g:

nameList = new List<object>();