Summary of methods for generating random passwords in php

When you want to generate a random password, you may first think of using the uniquid () function, but if we use array_rand () and range (), we can more perfectly implement

When you want to generate a random password, you may first think of using the uniquid () function, but if we use array_rand () and range (), this function can be implemented more perfectly.

Method 1: The code is as follows:

2. Header ("Content-type: text/html; charset = utf-8 ");
3. Function randCode ($ length ){
4. $ Ranges = array (range ('A', 'z'), range ('A', 'z'), range (1, 9 ));
5. $ Code = '';
6. For ($ I = 0; $ I <$ length; $ I ++ ){
7. $ Rkey = array_rand ($ ranges );
8. $ Vkey = array_rand ($ ranges [$ rkey]);
9. $ Code. = $ ranges [$ rkey] [$ vkey];
10. }
11. Return $ code;
12. }
13. Echo "www.phpfensi.com ";
14. Echo randCode (5); // outputs such as 3IxY8, E6HOv, and 1qHiy
15. ?>

Method 2

1. Generate a random integer in 33-126, for example, 35,

2. convert 35 to corresponding ASCII characters, for example, 35 #

3. Repeat steps 1 and 2 n and connect them to a n-bit password.

This algorithm mainly uses two functions. the mt_rand (int $ min, int $ max) function is used to generate random integers, where $ min-$ max is the ASCII code range, here, the range is 33-126. you can adjust the range as needed. for example, 97-122 characters in the ASCII code table correspond to English letters a-z. for details, refer to the ASCII code table. chr (int $ ascii) the function is used to convert the corresponding integer $ ascii to the corresponding character. the code is as follows:

1. Function create_password ($ pw_length = 8)
2. {
3. $ Randpwd = '';
4. For ($ I = 0; $ I <$ pw_length; $ I ++)
5. {
6. $ Randpwd. = chr (mt_rand (33,126 ));
7. }
8. Return $ randpwd;
9. }
10. // Call this function to pass the length parameter $ pw_length = 6
11. Echo create_password (6 );

Method 3: The code is as follows:

1. // Automatically generate a random user name for the user (length: 6-13)
2. Function create_password ($ pw_length = 4 ){
3. $ Randpwd = '';
4. For ($ I = 0; $ I <$ pw_length; $ I ++ ){
5. $ Randpwd. = chr (mt_rand (33,126 ));
6. }
7. Return $ randpwd;
8. }
9. Function generate_username ($ length = 6 ){
10. // Password character set, which can be any character you need
11. $ Chars = 'abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz0123456789! @ # $ % ^ & * ()-_ [] {}<> ~ '+ = ,.;:/? | ';
12. $ Password = '';
13. For ($ I = 0; $ I <$ length; $ I ++)
14. {
15. // Two character acquisition methods are provided here
16. // Use substr to intercept any character in $ chars;
17. // The second method is to take any element of the character array $ chars.
18. // $ Password. = substr ($ chars, mt_rand (0, strlen ($ chars)-1), 1 );
19. $ Password. = $ chars [mt_rand (0, strlen ($ chars)-1)];
20. }
21. Return $ password;
22. }
23. // Call this function
24. $ UserId = 'user'. generate_username (6 );
25. $ Pwd = create_password (9 );