Code One:
A function that generates a random password, which is a random string of lowercase letters and numbers, and can be customized in length. Relatively speaking, this is relatively simple
Copy Code code as follows:
<?php
/*
* PHP automatically generates a new password custom function (demo with instance)
applicable environment: php5.2.x /mysql 5.0.x
* */
Function Genpassword ($min = 5, $max = 8)
{ ;
$validchars = "abcdefghijklmnopqrstuvwxyz123456789";
$max _char= Strlen ($validchars) -1;
$length =mt_rand ($min, $max);
$ Password = "";
for ($i =0; $i < $length; $i)
{
&nb sp; $password. = $validchars [Mt_rand (0, $max _char)];
}
return $password;
}
echo "New password:". Genpassword (). <br> ";
echo" New password: ". Genpassword (5,10)." <br> ";
?>
The following summary of some examples of friends can refer to.
Example 1
The most concise way to build
Copy Code code as follows:
function Generatepassword ($length =8)
{
$chars = Array_merge (range (0,9),
Range (' A ', ' Z '),
Range (' A ', ' Z '),
Array ('! ', ' @ ', ' $ ', '% ', ' ^ ', ' & ', ' * '));
Shuffle ($chars);
$password = ';
For ($i =0 $i <8; $i + +) {
$password. = $chars [$i];
}
return $password;
}
Example 2
1. Generate a random integer, such as 35, in 33–126
2, convert 35 to the corresponding ASCII code characters, such as 35 corresponding #
3, repeat the above 1, 2 steps n times, connected to the N-bit password
Copy Code code as follows:
function Create_password ($PW _length = 8)
{
$randpwd = ';
for ($i = 0; $i < $PW _length; $i + +)
{
$randpwd. = Chr (Mt_rand (33, 126));
}
return $randpwd;
}
Call the function, passing the length parameter $pw_length = 6
Echo Create_password (6);
Instance
Copy Code code as follows:
<?php
Mt_srand (Double) microtime () * 1000000);
function Gen_random_password ($password _length = $generated _password = "") {
$valid _characters = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
$chars _length = strlen ($valid _characters)-1;
for ($i = $password _length; $i-;) {
$generated _password. = $valid _characters[mt_rand (0, $chars _length)];
$generated _password. = substr ($valid _characters, (Mt_rand ()% (strlen ($valid _characters)), 1);
}
return $generated _password;
}
? ><! DOCTYPE HTML PUBLIC "-//w3c//dtd HTML 4.01 transitional//en" "HTTP://WWW.W3.ORG/TR/HTML4/LOOSE.DTD" >
<title>php Password Generator v 4.0</title>
<style type= "Text/css" >
Body {
font-family:arial;
font-size:10pt;
}
</style>
<body>
<span style= "Font-weight:bold; font-size:15pt; " > Password Generator v4.0 by freemouse</span><br/><br/>
<?php
if (Isset ($_get[' password_length ')) {
if (Preg_match ("/([0-9]{1,8})/", $_get[' Password_length ')) {
Print ("Password generation succeeded: <br/>
<span style= "Font-weight:bold" > ". Gen_random_password ($_get[' password_length ')). "</span><br/><br/>n");
} else {
Print ("Incorrect password length!<br/><br/>n");
}
}
Print <<< End
Please generate the length of its specified build password for the password: <br/><br/>
<form action= "{$_server[' php_self ']}" method= "get" >
<input type= "text" name= "Password_length" >
<input type= "Submit" value= "Build" >
</form>
End
?>
</body>
Example 4
1, preset a string $chars, including A–z,a–z,0–9, as well as some special characters
2. Randomly take a character in a $chars string
3, repeat the second step n times, can get a length of n password
Copy Code code as follows:
function Generate_password ($length = 8) {
Password character set, you can add any character you need
$chars = ' abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz0123456789!@#$%^&* ()-_ []{}<>~ ' +=,.;:/?| ';
$password = ';
for ($i = 0; $i < $length; $i + +)
{
Here are two ways to get a character
The first is to use SUBSTR to intercept any one character in the $chars;
The second is to take any element $chars the character array
$password. = substr ($chars, Mt_rand (0, strlen ($chars)-1), 1);
$password. = $chars [Mt_rand (0, strlen ($chars)-1)];
}
return $password;
}
The test performance is not as good as the following
1, preset a character array $chars, including a–z,a–z,0–9, as well as some special characters
2. Randomly select $length elements from the array $chars by Array_rand ()
3, according to the acquired key array group $keys, from the array $chars out character stitching string. The disadvantage of this method is that the same characters are not repeated.
Copy Code code as follows:
function Make_password ($length = 8)
{
Password character set, you can add any character you need
$chars = Array (' A ', ' B ', ' C ', ' d ', ' e ', ' f ', ' g ', ' H ',
' I ', ' j ', ' K ', ' l ', ' m ', ' n ', ' o ', ' P ', ' Q ', ' R ', ' s ',
' t ', ' u ', ' V ', ' w ', ' x ', ' y ', ' z ', ' A ', ' B ', ' C ', ' D ',
' E ', ' F ', ' G ', ' H ', ' I ', ' J ', ' K ', ' L ', ' M ', ' N ', ' O ',
' P ', ' Q ', ' R ', ' S ', ' T ', ' U ', ' V ', ' W ', ' X ', ' Y ', ' Z ',
' 0 ', ' 1 ', ' 2 ', ' 3 ', ' 4 ', ' 5 ', ' 6 ', ' 7 ', ' 8 ', ' 9 ', '! ',
' @ ', ' # ', ' $ ', '% ', ' ^ ', ' & ', ' * ', ' (', ') ', '-', ' _ ',
' [', '] ', ' {', '} ', ' < ', ' > ', ' ~ ', ' ', ' + ', ' = ', ', ', ', ', ', ', '
'.', ';', ':', '/', '?', '|');
Randomly taking $length array element key name in a $chars
$keys = Array_rand ($chars, $length);
$password = ';
for ($i = 0; $i < $length; $i + +)
{
To concatenate $length array elements into strings
$password. = $chars [$keys [$i]];
}
return $password;
}
