Generating a 4–8 digit random number

Question

Random random = new Random();
int password = random.Next(10000);

This generates 2-digit and 3-digit numbers also. How do I generate a 4–8 digit random number in C#?

Answer 1

从最小的4位数字开始，以最小的9位数字结尾（独家）：

int password = random.Next(1000, 100000000);

Answer 2

You could also make a method:

public static int GetRandom(int minDigits, int maxDigits)
{
    if (minDigits < 1 || minDigits > maxDigits)
        throw new ArgumentOutOfRangeException();

    return (int)random.Next(Math.Pow(10, minDigits - 1), Math.Pow(10, maxDigits - 1));
}

Answer 3

To cover all your bases (numbers under 1000 such as 0002)

Random RandomPIN = new Random();
var RandomPINResult = RandomPIN.Next(0, 9999).ToString();
RandomPINResult = RandomPINResult.PadLeft(4, '0');

Answer 4

new Random（Guid.NewGuid（）。GetHashCode（））。Next（0,9999）.ToString（“D4”）