How do I generate a random integer in C#?

How do I generate a random integer in C#?

Random r = new Random();
int n = r.Next();

The numbers generated by the inbuilt `Random` class (System.Random) generates pseudo random numbers.

If you want true random numbers, the closest we can get is "secure Pseudo Random Generator" which can be generated by using the Cryptographic classes in C# such as `RNGCryptoServiceProvider`.

Even so, if you still need *true* random numbers you will need to use an external source such as devices accounting for radioactive decay as a seed for an random number generator. Since, by definition, any number generated by purely algorithmic means cannot be truly random.

I wanted to add a cryptographically secure version:

RNGCryptoServiceProvider Class ([MSDN][1] or [dotnetperls][2])

It implements IDisposable.

using (RNGCryptoServiceProvider rng = new RNGCryptoServiceProvider())
{
byte[] randomNumber = new byte[4];//4 for int32
rng.GetBytes(randomNumber);
int value = BitConverter.ToInt32(randomNumber, 0);
}

[1]:

[To see links please register here]

[2]:http://www.dotnetperls.com/rngcryptoserviceprovider

Numbers calculated by a computer through a deterministic process, cannot, by definition, be random.

If you want a genuine random numbers, the randomness comes from atmospheric noise or radioactive decay.

You can try for example RANDOM.ORG (it reduces performance)

Why not use `int randomNumber = Random.Range(start_range, end_range)` ?