Random Numbers in C#

re: Random Numbers in C#

kame — Sat, 01 Aug 2009 09:46:18 GMT

p a prime modulus, where 2L–1 < p < 2L, and L is the bit length of p. Values for L are

provided in Section 4.2.

q a prime divisor of (p – 1), where 2N–1 < q < 2 N, and N is the bit length of q. Values for

are provided in Section 4.2.

g a generator of the subgroup of order q mod p, such that 1 < g < p.

x the private key that must remain secret; x is a randomly or pseudorandomly generated

integer, such that 0 < x < q, i.e., x is in the range [1, q–1].

y the public key, where y = gx mod p.

k a secret number that is unique to each message; k is a randomly or pseudorandomly

generated integer, such that 0 < k < q, i.e., k is in the range [1, q–1].

r = (gk mod p) mod q.

z = the leftmost min(N, outlen) bits of Hash(M).

s = ( k −1 (z + xr)) mod q.

re: Random Numbers in C#

akhil — Mon, 13 Oct 2008 08:01:57 GMT

i m doing in an online Examinition Project in C# Dot Net 2005.I want to call all questions (Unique) randomly from SQL server.

Can u help me to solve my problem.

Plz Help.

re: Random Numbers in C#

Balamurugan — Wed, 02 Jul 2008 09:04:04 GMT

I have to generate random numbers,its should not be repeated...

re: Random Numbers in C#

Free News Website — Wed, 19 Dec 2007 06:10:25 GMT

Appreciate the article. What's the best way to generate the seed? I was thinking of using CPU ticks.

re: Random Numbers in C#

Yining Chen — Fri, 10 Aug 2007 16:01:35 GMT

why not just use a singleton pattern to wrap around the Random class? that'll solve all your concurrency issues, as well as giving you a global RNG.

re: Random Numbers in C#

Sultan Saadat — Sun, 22 Jul 2007 18:56:40 GMT

Simplest way

private int RandomNumber(int min, int max)

{

Random random = new Random();

return random.Next(min, max);

}

re: Random Numbers in C#

roflmao — Wed, 30 May 2007 10:07:57 GMT

hbajksdhajksdh

This is like, so random! Some Randomness from System.Random

TrackBack — Wed, 09 Mar 2005 21:02:00 GMT

re: Random Numbers in C#

Daniel Jin — Thu, 06 May 2004 23:04:00 GMT

that solves one problem. in your code, you would also run into a race condition in the Random class instantiation. Two threads, concurrently, could check the cache before an instance is created, both will retrieve *null*, both will create new instances ... you would need to synchronize that too.

re: Random Numbers in C#

Eli Robillard — Thu, 06 May 2004 20:41:00 GMT

Daniel: Good point, I've added a lock {} as recommended by Brad Abrams' blog.

Ryan: Another point recommended by Brad, though that class is an abstract which is intended to be inherited by other implementations, it can't be used directly. The remarks in the docs offer this: "For an implementation of a cryptographic random number generator, use the derived class RNGCryptoServiceProvider."

As a solution, it seems to me somewhere between overkill and passing the buck. But, for those so inclined: http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpref/html/frlrfsystemsecuritycryptographyrngcryptoserviceproviderclasstopic.asp

Great comments!