C# || How can i generate a random number between 0 and ulong.MaxValue with the best performance [duplicate]

This question already has an answer here:

• Random number in long range, is this the way? 13 answers

I am trying to give "Unique IDs" and using Ints its "risky" so im using Ulongs. Now...

How could I generate a value between 0 and ulong.max ?

Should be pretty easy...right?

One line of code?