How do I check if string exist in list?

Question

I'm working out on a random 4 length number that won't repeat so I'm trying to do a list with the numbers already tried then check if the number is already in the list if not add else generate another one.

Sergio Fonseca · Answer

Thank you man I'm now modifying a bit to work in my application.

Alan · Answer

Try this code: using System; using System.Collections.Generic; class Program { static Random rand = new Random(); static void Main() { Console.Write (How many unique 4 digit random numbers do you want to generate? : ); int x = int.Parse(Console.ReadLine()); List numbers = new List (x); numbers.Add(rand.Next(010000)); // first one must be unique bool unique; int num = 0; for (int i = 1; i { unique = false; while(!unique) { num = rand.Next(010000); if (numbers.IndexOf(num) == -1) // if unique { numbers.Add(num); unique = true; } } } Console.WriteLine(
The {0} random numbers are :
 x); foreach(int number in numbers) { Console.WriteLine(number.ToString(D4)); } Console.ReadKey(); } }