Invitation code algorithm, invitation Algorithm

Invitation code algorithm, invitation Algorithm

The website wants to register an invitation code. I have found many algorithms on the Internet to generate 6-digit invitation codes, but none of them are very satisfied. I always think they are not perfect. I have made some improvements based on an algorithm on the Internet. I also hope you will be guided by experienced masters. I am also a beginner in programming. I wrote it down to record my learning process as I grew up !!!

Public string GetInvitationCode ()

{

// Custom hexadecimal notation with a length of 34. 0 and 1 are easy to confuse with o and l, and are not included in the system.

Char [] r = new char [] {'Q', 'w', 'E', '8', 'A', 's', '2 ', 'D', 'z', 'x', '9', 'C', '7', 'P', 'O', '5', 'I ', 'k', '3', 'M', 'J', 'U', 'F', 'R', '4', 'V', 'y ', 'l', 't', 'n', '6', 'B', 'G', 'H '};

Char [] B = new char [] {'Q', 'w', 'E', '5', 'A', 's', '3 ', 'D', 'z', 'x', '8', 'C', '2', 'P', 'O', '4', 'I ', 'k', '9', 'M', 'J', 'U', 'F', 'R', '6', 'V', 'y ', 'T', 'n', '7', 'B', 'G', 'H '};

Char [] buf = new char [33];

Int s = 6; // generates a six-digit invitation code.

Int binLen = r. Length;

Int charPos = 33;

// Use the current number of milliseconds as the standard

Int id = DateTime. Now. Millisecond;

While (id/binLen> 0)

{

Int k = (int) (id % binLen );

Buf [-- charPos] = r [k];

Id/= binLen;

}

Buf [-- charPos] = r [(int) (id % binLen)];

String str = new String (buf, charPos, (33-charPos ));

// If the length is not 6 characters long, the system automatically performs random completion.

If (str. Length <s)

{

StringBuilder sb = new StringBuilder ();

Random rd = new Random ();

For (int I = 1; I <= s-str. Length; I ++)

{

Sb. Append (B [rd. Next (33)]);

}

Str + = sb. ToString ();

}

Return str. ToUpper ();

}