Get class name from file
Solution 1
There are multiple possible solutions to this problem, each with their advantages and disadvantages. Here they are, it's up to know to decide which one you want.
Tokenizer
This method uses the tokenizer and reads parts of the file until it finds a class definition.
Advantages
- Do not have to parse the file entirely
- Fast (reads the beginning of the file only)
- Little to no chance of false positives
Disadvantages
- Longest solution
Code
$fp = fopen($file, 'r');
$class = $buffer = '';
$i = 0;
while (!$class) {
if (feof($fp)) break;
$buffer .= fread($fp, 512);
$tokens = token_get_all($buffer);
if (strpos($buffer, '{') === false) continue;
for (;$i<count($tokens);$i++) {
if ($tokens[$i][0] === T_CLASS) {
for ($j=$i+1;$j<count($tokens);$j++) {
if ($tokens[$j] === '{') {
$class = $tokens[$i+2][1];
}
}
}
}
}
Regular expressions
Use regular expressions to parse the beginning of the file, until a class definition is found.
Advantages
- Do not have to parse the file entirely
- Fast (reads the beginning of the file only)
Disadvantages
- High chances of false positives (e.g.:
echo "class Foo {";)
Code
$fp = fopen($file, 'r');
$class = $buffer = '';
$i = 0;
while (!$class) {
if (feof($fp)) break;
$buffer .= fread($fp, 512);
if (preg_match('/class\s+(\w+)(.*)?\{/', $buffer, $matches)) {
$class = $matches[1];
break;
}
}
Note: The regex can probably be improved, but no regex alone can do this perfectly.
Get list of declared classes
This method uses get_declared_classes() and look for the first class defined after an include.
Advantages
- Shortest solution
- No chance of false positive
Disadvantages
- Have to load the entire file
- Have to load the entire list of classes in memory twice
- Have to load the class definition in memory
Code
$classes = get_declared_classes();
include 'test2.php';
$diff = array_diff(get_declared_classes(), $classes);
$class = reset($diff);
Note: You cannot simply do end() as others suggested. If the class includes another class, you will get a wrong result.
This is the Tokenizer solution, modified to include a $namespace variable containing the class namespace, if applicable:
$fp = fopen($file, 'r');
$class = $namespace = $buffer = '';
$i = 0;
while (!$class) {
if (feof($fp)) break;
$buffer .= fread($fp, 512);
$tokens = token_get_all($buffer);
if (strpos($buffer, '{') === false) continue;
for (;$i<count($tokens);$i++) {
if ($tokens[$i][0] === T_NAMESPACE) {
for ($j=$i+1;$j<count($tokens); $j++) {
if ($tokens[$j][0] === T_STRING) {
$namespace .= '\\'.$tokens[$j][1];
} else if ($tokens[$j] === '{' || $tokens[$j] === ';') {
break;
}
}
}
if ($tokens[$i][0] === T_CLASS) {
for ($j=$i+1;$j<count($tokens);$j++) {
if ($tokens[$j] === '{') {
$class = $tokens[$i+2][1];
}
}
}
}
}
Say you have this class:
namespace foo\bar {
class hello { }
}
...or the alternative syntax:
namespace foo\bar;
class hello { }
You should have the following result:
var_dump($namespace); // \foo\bar
var_dump($class); // hello
You could also use the above to detect the namespace a file declares, regardless of it containing a class or not.
Solution 2
You can make PHP do the work by just including the file and get the last declared class:
$file = 'class.php'; # contains class Foo
include($file);
$classes = get_declared_classes();
$class = end($classes);
echo $class; # Foo
If you need to isolate that, wrap it into a commandline script and execute it via shell_exec:
$file = 'class.php'; # contains class Foo
$class = shell_exec("php -r \"include('$file'); echo end(get_declared_classes());\"");
echo $class; # Foo
If you dislike commandline scripts, you can do it like in this question, however that code does not reflect namespaces.
Solution 3
$st = get_declared_classes();
include "classes.php"; //one or more classes in file, contains class class1, class2, etc...
$res = array_values(array_diff_key(get_declared_classes(),$st));
print_r($res); # Array ([0] => class1 [1] => class2 [2] ...)
Solution 4
I modified Nette\Reflection\AnnotationsParser that so it returns an array of namespace+classname that are defined in the file
$parser = new PhpParser();
$parser->extractPhpClasses('src/Path/To/File.php');
class PhpParser
{
public function extractPhpClasses(string $path)
{
$code = file_get_contents($path);
$tokens = @token_get_all($code);
$namespace = $class = $classLevel = $level = NULL;
$classes = [];
while (list(, $token) = each($tokens)) {
switch (is_array($token) ? $token[0] : $token) {
case T_NAMESPACE:
$namespace = ltrim($this->fetch($tokens, [T_STRING, T_NS_SEPARATOR]) . '\\', '\\');
break;
case T_CLASS:
case T_INTERFACE:
if ($name = $this->fetch($tokens, T_STRING)) {
$classes[] = $namespace . $name;
}
break;
}
}
return $classes;
}
private function fetch(&$tokens, $take)
{
$res = NULL;
while ($token = current($tokens)) {
list($token, $s) = is_array($token) ? $token : [$token, $token];
if (in_array($token, (array) $take, TRUE)) {
$res .= $s;
} elseif (!in_array($token, [T_DOC_COMMENT, T_WHITESPACE, T_COMMENT], TRUE)) {
break;
}
next($tokens);
}
return $res;
}
}
Solution 5
Thanks to some people from Stackoverflow and Github, I was able to write this amazing fully working solution:
/**
* get the full name (name \ namespace) of a class from its file path
* result example: (string) "I\Am\The\Namespace\Of\This\Class"
*
* @param $filePathName
*
* @return string
*/
public function getClassFullNameFromFile($filePathName)
{
return $this->getClassNamespaceFromFile($filePathName) . '\\' . $this->getClassNameFromFile($filePathName);
}
/**
* build and return an object of a class from its file path
*
* @param $filePathName
*
* @return mixed
*/
public function getClassObjectFromFile($filePathName)
{
$classString = $this->getClassFullNameFromFile($filePathName);
$object = new $classString;
return $object;
}
/**
* get the class namespace form file path using token
*
* @param $filePathName
*
* @return null|string
*/
protected function getClassNamespaceFromFile($filePathName)
{
$src = file_get_contents($filePathName);
$tokens = token_get_all($src);
$count = count($tokens);
$i = 0;
$namespace = '';
$namespace_ok = false;
while ($i < $count) {
$token = $tokens[$i];
if (is_array($token) && $token[0] === T_NAMESPACE) {
// Found namespace declaration
while (++$i < $count) {
if ($tokens[$i] === ';') {
$namespace_ok = true;
$namespace = trim($namespace);
break;
}
$namespace .= is_array($tokens[$i]) ? $tokens[$i][1] : $tokens[$i];
}
break;
}
$i++;
}
if (!$namespace_ok) {
return null;
} else {
return $namespace;
}
}
/**
* get the class name form file path using token
*
* @param $filePathName
*
* @return mixed
*/
protected function getClassNameFromFile($filePathName)
{
$php_code = file_get_contents($filePathName);
$classes = array();
$tokens = token_get_all($php_code);
$count = count($tokens);
for ($i = 2; $i < $count; $i++) {
if ($tokens[$i - 2][0] == T_CLASS
&& $tokens[$i - 1][0] == T_WHITESPACE
&& $tokens[$i][0] == T_STRING
) {
$class_name = $tokens[$i][1];
$classes[] = $class_name;
}
}
return $classes[0];
}
Daniel
Updated on July 09, 2022Comments
-
Daniel almost 2 years
I have a php file which contains only one class. how can I know what class is there by knowing the filename? I know I can do something with regexp matching but is there a standard php way? (the file is already included in the page that is trying to figure out the class name).