PHP_ Making Verification Code

PHP makes a verification code, mainly using array-related functions

1<?PHP2     Header("Content-type:text/html;charset=utf-8");3     //set up 3 ranges of arrays4     $shuzi=Range(0,9);5     $zimuda=Range(' A ', ' Z ');6     $zimuxiao=Range(' A ', ' Z ');7 8     //Merge these 3 arrays into a new array9     $arr=Array_merge($shuzi,$zimuxiao,$zimuda);Ten  One     //traversing a new array A     foreach($arr  as $key=$value) { -         //if the element in the new array contains the following word, it is deleted (unset); -         if($value= = ' 0 ' | |$value= = ' 1 ' | |$value= = ' 2 ' | |$value= = ' O ' | |$value= = ' O ' the||$value= = ' I ' | |$value= = ' I ' | |$value= = ' Z ' | |$value= = ' Z ' | |$value= = ' L '){ -             //Delete the key, and the value is deleted -             unset($arr[$key]); -             } +         } -  +     //The array element is scrambled, its key value follows the element is disturbed A     Shuffle($arr); at     //4 Key values of the original array are randomly taken out -     $arr _rand=Array_rand($arr, 4); -     //Pass the key of the original array through the output, get 4 random verification code -     foreach($arr _rand  as $value) { -         Echo $arr[$value]; -     } in  -     //Optimization: 0,1,2 These 3 numbers originally need to exclude, just in the array of the first, continuous, in the definition of the range array can not write, directly from 3, reduce if judgment; uppercase and lowercase z can not be written at the end

PHP_ Making Verification Code