list all defined constants from a file in php - php

Question

I have some php files that includes some language constants
define("_SEARCH","Search");
define("_LOGIN","Login");
define("_WRITES","writes");
define("_POSTEDON","Posted on");
define("_NICKNAME","Nickname");
now I need to read each file and list all constants and their values
and to return an output like this :
constant name :
value is :
so I think there should be function to list all defined constants of a given php file.
I'm aware of functions like token_get_all or get_defined_constants but i wasn't able to do it.

Answer 1

If the files do contain nothing but define statements, you can use get_defined_constants:
function getUserDefinedConstants() {
$constants = get_defined_constants(true);
return (isset($constants['user']) ? $constants['user'] : array());
}
$constantsBeforeInclude = getUserDefinedConstants();
include('file.php');
$constantsAfterInclude = getUserDefinedConstants();
$newConstants = array_diff_assoc($constantsAfterInclude, $constantsBeforeInclude);
What it does is basically: get_defined_constants(true) gives us an array of arrays with all available constants, sorted by sections (core, user, ..) - the array under the key 'user' gives us all user-defined constants that we defined in our php code using define, up to that point. array_diff_assoc gives us the difference between this array before and after the file got included.. and that is exactly a list of all constants that got defined in that specific file (as long as there is none of the declarations a duplicate, meaning a constant with that exact name has been defined before - but this would cause an error anyway).

Answer 2

this is the php script you need:
<?php
//remove comments
$Text = php_strip_whitespace("your_constants_file.php");
$Text = str_replace("<?php","",$Text);
$Text = str_replace("<?","",$Text);
$Text = str_replace("?>","",$Text);
$Lines = explode(";",$Text);
$Constants = array();
//extract constants from php code
foreach ($Lines as $Line) {
//skip blank lines
if (strlen(trim($Line))==0) continue;
$Line = trim($Line);
//skip non-definition lines
if (strpos($Line,"define(")!==0) continue;
$Line = str_replace("define(\"","",$Line);
//get definition name & value
$Pos = strpos($Line,"\",\"");
$Left = substr($Line,0,$Pos);
$Right = substr($Line,$Pos+3);
$Right = str_replace("\")","",$Right);
$Constants[$Left] = $Right;
}
echo "<pre>";
var_dump($Constants);
echo "</pre>";
?>
The result will be something similar to this:
array(5) {
["_SEARCH"]=>
string(6) "Search"
["_LOGIN"]=>
string(5) "Login"
["_WRITES"]=>
string(6) "writes"
["_POSTEDON"]=>
string(9) "Posted on"
["_NICKNAME"]=>
string(8) "Nickname"
}

Answer 3

Late to the game here but I had a similar issue. You could use an include() substitute/wrapper function that logs constants in an accessible global array.
<?php
function include_build_page_constants($file) {
global $page_constants ;
$before = get_defined_constants(true);
include_once($file);
$after = get_defined_constants(true);
if ( isset($after['user']) ) {
if ( isset($before['user']) ) {
$current = array_diff_assoc($after['user'],$before['user']);
}else{
$current = $after['user'];
}
$page_constants[basename($file)]=$current;
}
}
include_and_build_page_constants('page1.php');
include_and_build_page_constants('page2.php');
// test the array
echo '<pre>'.print_r($page_constants,true).'</pre>';
?>
This will result in something like:
Array
(
[page1.php] => Array
(
[_SEARCH] => Search
[_LOGIN] => Login
[_WRITES] => writes
[_POSTEDON] => Posted on
[_NICKNAME] => Nickname
)
[page2.php] => Array
(
[_THIS] => Foo
[_THAT] => Bar
)
)

Answer 4

Assuming that you want to do this on runtime, you should take a look at PHP Reflection, specifically at the ReflectionClass::getConstants() which lets you do exactly what you seem to want.

Answer 5

I too had the same problem. I went from jondinham's suggestion, but I prefer to use regex, as it is a bit easier to control and flexible. Here's my version of the solution:
$text = php_strip_whitespace($fileWithConstants);
$text = str_replace(array('<?php', '<?', '?>'), '', $text);
$lines = explode(";", $text);
$constants = array();
//extract constants from php code
foreach ($lines as $line) {
//skip blank lines
if (strlen(trim($line)) == 0)
continue;
preg_match('/^define\((\'.*\'|".*"),( )?(.*)\)$/', trim($line), $matches, PREG_OFFSET_CAPTURE);
if ($matches) {
$constantName = substr($matches[1][0], 1, strlen($matches[1][0]) - 2);
$constantValue = $matches[3][0];
$constants[$constantName] = $constantValue;
}
}
print_r($constants);