How to implement PHP verification code? (Pictures + Videos)

This article mainly introduces to you the specific ideas and methods of PHP to implement verification code.

In our PHP project development process, the verification code process in the background login interface is basically indispensable, and the purpose of generating verification codes is mainly to prevent malicious registration.

For PHP novices, verification code production is also a basic knowledge point that must be learned. Of course, there are many verification codes, such as numeric and letter combination verification codes, Chinese verification codes, digital verification codes, picture verification codes, etc.

Below we will introduce a simple number-letter combination verification code method through specific code examples.

First we create three ranges of arrays and merge these three arrays into a new array. The code is as follows:

<?php
$shuzi = range(0, 9);
$zimuda = range(&#39;A&#39;, &#39;Z&#39;);
$zimuxiao = range(&#39;a&#39;, &#39;z &#39;);
$arr = array_merge($shuzi, $zimuxiao, $zimuda);
echo "<pre class="brush:php;toolbar:false">";
var_dump($arr);

Accessed through the browser, the content of the new array is as follows:

array (size=62)
  0 => int 0
  1 => int 1
  2 => int 2
  3 => int 3
  4 => int 4
  5 => int 5
  6 => int 6
  7 => int 7
  8 => int 8
  9 => int 9
  10 => string 'a' (length=1)
  11 => string 'b' (length=1)
  12 => string 'c' (length=1)
  13 => string 'd' (length=1)
  14 => string 'e' (length=1)
  15 => string 'f' (length=1)
  16 => string 'g' (length=1)
  17 => string 'h' (length=1)
  18 => string 'i' (length=1)
  19 => string 'j' (length=1)
  20 => string 'k' (length=1)
  21 => string 'l' (length=1)
  22 => string 'm' (length=1)
  23 => string 'n' (length=1)
  24 => string 'o' (length=1)
  25 => string 'p' (length=1)
  26 => string 'q' (length=1)
  27 => string 'r' (length=1)
  28 => string 's' (length=1)
  29 => string 't' (length=1)
  30 => string 'u' (length=1)
  31 => string 'v' (length=1)
  32 => string 'w' (length=1)
  33 => string 'x' (length=1)
  34 => string 'y' (length=1)
  35 => string 'z' (length=1)
  36 => string 'A' (length=1)
  37 => string 'B' (length=1)
  38 => string 'C' (length=1)
  39 => string 'D' (length=1)
  40 => string 'E' (length=1)
  41 => string 'F' (length=1)
  42 => string 'G' (length=1)
  43 => string 'H' (length=1)
  44 => string 'I' (length=1)
  45 => string 'J' (length=1)
  46 => string 'K' (length=1)
  47 => string 'L' (length=1)
  48 => string 'M' (length=1)
  49 => string 'N' (length=1)
  50 => string 'O' (length=1)
  51 => string 'P' (length=1)
  52 => string 'Q' (length=1)
  53 => string 'R' (length=1)
  54 => string 'S' (length=1)
  55 => string 'T' (length=1)
  56 => string 'U' (length=1)
  57 => string 'V' (length=1)
  58 => string 'W' (length=1)
  59 => string 'X' (length=1)
  60 => string 'Y' (length=1)
  61 => string 'Z' (length=1)

The range function in PHP is mainly used here, which means to create an array based on the range and contain the specified elements. The array_merge function means merging one or more arrays.

Then the new array elements are scrambled through the shuffle function, and their KEY values ​​are scrambled following the elements. Then use the array_rand function to randomly extract the 4 key values ​​​​of the original array. Finally, the keys of the original array are traversed and output, and 4 random verification codes are obtained. The code is as follows:

<?php
$shuzi = range(0, 9);
$zimuda = range(&#39;A&#39;, &#39;Z&#39;);
$zimuxiao = range(&#39;a&#39;, &#39;z &#39;);
$arr = array_merge($shuzi, $zimuxiao, $zimuda);
shuffle($arr);
$arr_rand = array_rand($arr, 4);
foreach ($arr_rand as $value) {
    echo $arr[$value];
}

Note:

shuffle: shuffle the array.

array_rand: Randomly take out one or more units from the array

Finally accessed through the browser, each refresh will get a new random verification code as follows:

This article is a detailed introduction to the ideas and methods of PHP to implement verification code. It is very simple and easy to understand. I hope it will be useful to friends who need it. help!

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