Here I have written the code to create random Password/Number using uppercase, lowercase, digits, and special characters.

.Net provides the class Random , which has three methods - Next, NextBytes, and NextDouble.
  • Next()- Next method returns a random number.
  • NextBytes()-NextBytes returns an array of bytes filled with random numbers.
  • NextDouble()- returns a random number between 0.0 and 1.0.
I have used NextDouble.

Use

We can use this random password for One Time Password (OTP) or Temporary Password.

Code written in Console Application
  1. //Libraries
  2. using System;
  3. using System.Collections.Generic;
  4. using System.Linq;
  5. using System.Text;
  6. using System.Threading.Tasks;
  7. namespace PasswordPractice {
  8. class PasswordCreate {
  9. //Tis function is making the Random Password
  10. public string makeRandomPassword(int length) {
  11. string UpperCase = "QWERTYUIOPASDFGHJKLZXCVBNM";
  12. string LowerCase = "qwertyuiopasdfghjklzxcvbnm";
  13. string Digits = "1234567890";
  14. string allCharacters = UpperCase + LowerCase + Digits;
  15. //Random will give random charactors for given length
  16. Random r = new Random();
  17. String password = "";
  18. for (int i = 0; i < length; i++) {
  19. double rand = r.NextDouble();
  20. if (i == 0) {
  21. password += UpperCase.ToCharArray()[(int) Math.Floor(rand * UpperCase.Length)];
  22. } else {
  23. password += allCharacters.ToCharArray()[(int) Math.Floor(rand * allCharacters.Length)];
  24. }
  25. }
  26. Console.WriteLine(password);
  27. Console.ReadLine();
  28. return password;
  29. }
  30. static void Main(string[] args) {
  31. //User Input
  32. Console.WriteLine("Enter length of password");
  33. string len = Console.ReadLine();
  34. PasswordCreate n = new PasswordCreate();
  35. //Call the method in main method
  36. n.makeRandomPassword(Convert.ToInt32(len));
  37. }
  38. }
  39. }
Output of Given Code



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