PHP

Script language for dynamic web-pages. The syntax and concepts used are similar to Perl

Loop over an associative array (hash):

 
foreach ( $_POST as $key => $value ) {
            echo $key.' '.$value.' '.$_POST[$key].'<br>';
        }

Limited number of loops:

 
for ($i = 0; $i <= 6; $i++) {
  echo "Loop number: $i ";
}

escapeshellcmd(shellcommand)

Return the shellcommand with everything that might confuse the shell escaped.

exec(<cmd>,<outputarray>,<returnvar>)

Executed <cmd> in the shell, append the command output to he array <outputarray> and set <returnvar> to the returnvalue of the command.

Also the last line of the command output is returned

shell_exec(<cmd>)

Execute <cmd> (output from excapedshellcmd) in the shell, return the command output.

date("Y-m-d h:i:s")

Current timestamp (YYYY-mm-dd HH:MM:SS)

strpos($string, $search,$start)

Return position of $search exists in $string. When it is not in, return FALSE. Start searching at position $start (optional). Simple test on strpos - if (strpos(x,y)) {} - does not differ between position 0 and FALSE. Test on position 2 or count from the end by setting $start to a negative value (possible since PHP7.1).

preg_match($pattern, $string)

Return 1 if $pattern exists in $string

str_replace($old,$new,$string)

Replace $old with $new in $string

Functions

All variables are local to the function. You have to pass everything it needs.

<?php
function func1($arg1, $arg2)
{
    <codeblock>
    return $value;
}
?>

Arrays

arr1 = ( val1, val2, val3 )

Create an indexed array. The keys are the range 0..arraylength.

$arr1 = array(key1=>val1, key2=>val2, key3=>val3)

$arr2[key1] = val1

Create an associative array (like a hash in perl)

count(arr1)

Return the number of elements (length) of an array

foreach($arr1 as $value) { codeblock }

Loop over an indexed array

foreach($arr1 as $key => $value) { codeblock }

Loop over an associative array

Install

On debian (and its derivates)

apt-get install php-fpm php-mysql

Install php7 and mysql support

Fix php security by editing /etc/php/7.0/fpm/php.ini

Uncomment line with cgi.fix_pathinfo and set it to 0