Random.Next() sometimes returns same number in separate threads

Question

I have the following class

class Program
{
   static Random _Random = new Random();

   static void Main(string[] args)
   {
      ...
      for (int i = 0;          


        

Answer 1

Your example code only shows one use of _Random per thread. Assuming this is the case, you could also generate the random number in the main for loop and pass the random number into each thread as a parameter.

 for (int i = 0; i < no_threads; ++i)
 {
      var thread = new Thread(new ThreadStart(Send));
      thread.Start(_Random.Next(999999));
 }

and then modify your thread function to accept the parameter:

 static void Send(int device_id)
 {
    ...
    //int device_id = _Random.Next(999999);
    ...
 }