1  namespace Utils
 2  {
 3      public class NumberSource
 4      {
 5          private readonly object @lock = new object();
 6          private int number;
 7  
 8          public NumberSource(int start)
 9          {
10              number = start;
11          }
12  
13          public int GetNextNumber()
14          {
15              var n = -1;
16              lock (@lock)
17              {
18                  n = number;
19                  number++;
20              }
21              return n;
22          }
23      }
24  }