While converting list to dictionary and vice versa getting runtime error " StackOverflowException."

Question

I am new to C# Programming and I don't know How to convert list to dictionary and vice versa and I am getting an runtime error called " StackOverflowException." Can anyone help me out or if anyone knows the solution please let me know.

Thanks in advance.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Assign2
{
    class Conversion
    {
        
        
    }
    class Program
    {
        static void Main(string[] args)
        {
            Conversion conversion = new Conversion();
            var list = new List<string> { "Demo1","Demo2","Demo3","Demo4"};
            var dictionary = conversion.ListToDictionary(list);
            foreach (var item in dictionary)
            {
                Console.WriteLine($"{item.Key}, {item.Value}");
            }
            var convertedList = conversion.DictionaryToList(dictionary);
            foreach (var item in convertedList)

            {
                Console.WriteLine($"{item}");
            }
            Console.ReadLine();
        }
    }
}

you dont need to use conversion, you can directly convert list to dictionary by specifying key. For example : var myDict = list.ToDictionary(keySelector: m => m.Id); — zaakm, Aug 17 '22 at 08:28
This method calls itself `ListToDictionary` -> endless loop :-O — Markus Meyer, Aug 17 '22 at 08:29
you can further look at this for inspiration : https://stackoverflow.com/questions/687313/building-a-dictionary-of-counts-of-items-in-a-list/687370 — zaakm, Aug 17 '22 at 08:39

score 1 · Answer 1 · answered Aug 17 '22 at 08:26

ListToDictionary is calling itself and nothing is stopping it apparently. So it will call itself again and again and again... Until a stackoverflow exception because there will be too much call.

    public IDictionary<string,int> ListToDictionary(IList<string> list)
    {
        
            return ListToDictionary(list);
        
    }

The best way to convert a list to a dictionary is to use the "ToDictionary" extension method.

list.ToDictionary(item => item, item => item)

But in your case you're using a List of strings and a dictionary is a key/value set so what are you expecting in the end? Are the value in the list the keys or the values of the dictionary?

While converting list to dictionary and vice versa getting runtime error " StackOverflowException."

1 Answers1