Why do I need to initialize a new Random () with unchecked (Environment.TickCount * 31)?

Question

I found this instance initialization Random:

var random = new Random(unchecked(Environment.TickCount * 31));

Why not just use it new Random()?

Answer 1

The keyword uncheckeddoes not allow an exception to be thrown when the calculation overflows Environment.TickCount * 31.

The resulting calculation is essentially a random integer (it throws out a bunch of high bits), which is used to seed the random number generator.

Please note that Reference Source for Random has this code as its constructor without parameters:

public Random() 
    : this(Environment.TickCount) {
  }