Php if global exists

Checking for the Existence of a Global Class within a Namespace in PHP

Upon checking if the module has the correct class, an error is generated that points to the spl_autoload require_once row triggered by the class_exists function. Despite adding a «manage» folder to the articlelist module, no changes were observed. The project contains several modules, each with its own folder, with some featuring administrative functions and others displaying menus in the admin panel under the «manage» submenu, with the class always being Admin.php.

PHP — Check if global class exists inside namespace

Is it possible to verify the existence of a global variable \ \ \ \ \ class\ exists\ \ \ \ containing \ \ \ \ \ class_exists\ \ \ \ while being in the namespace of a different class? As an instance:

The class is defined globally.

It is possible that you have encountered an error in your previous attempts, such as the class being not declared in the scope. Have you forgotten to include it? To confirm, I ran a test.

It is not surprising that the output is «1». Therefore, it is recommended to verify your include paths.

Php — How to check if class exists within a namespace?, In order to check class you must specify it with namespace, full path: namespace Foo; class Bar < >and. var_dump (class_exists (‘Bar’), class_exists (‘\Foo\Bar’)); //false, true. -i.e. you must specify full path to class. You defined it in your namespace and not in global context. However, if you do import the class within the namespace like Code sampleuse XXX\Driver\Driver;if (class_exists(Driver::class)) <>Feedback

How to check if class exists within a namespace

How to check if class exists within a namespace — PHP [ Ext for Developers : https://www.hows.tech/p/recommended.html ] How to check if class exists within

Why I can’t stop throwing error in PHP when checking if class exists?

I have a colossal project in which all classes are loaded automatically using the \ \ \ \ \ spl_autoload_register\ \ \ \ command.

spl_autoload_register(function ($className) < try < require_once __DIR__ . DIRECTORY_SEPARATOR . str_replace("\\", DIRECTORY_SEPARATOR, $className) . ".php"; >catch (Exception $exception) < >>); 

Everything is functioning properly. Within the project, there are several «modules» that are stored in separate folders. Some of these modules contain administrative functions, while others have menus that appear in the admin panel. These menus are located in the «manage» submenu and the corresponding class is always named Admin.php.

foreach (glob(_modules_Path . "*") as $module) < if (is_dir($module)) < $classname = "vojjin\\modules\\" . basename($module) . "\\manage\\Admin"; try < if (class_exists($classname)) < if (method_exists($classname, "getAdminMenu")) < $out .= (new $classname())->getAdminMenu(); > > > catch (\Exception $e) <> > > 

Upon verifying the suitability of the module’s class, an error is indicated at \ \ \ \ \ spl_autoload\ \ \ \ due to the firing of the require_once row from invoking the class_exists function.

Fatal error: require_once(): Failed opening required '. \vojjin\modules\articlelist\manage\Admin.php' (include_path='.;C:\php\pear') in . 

Despite my attempts to create a «manage» folder within the articlelist module, no changes seem to occur. Despite implementing try/catch statements, PHP is consistently generating errors, indicating a lack of responsiveness to my commands. Do you have any suggestions?

To resolve the issue, I suggest using an if file_exists statement instead of the try catch block.

spl_autoload_register(function ($className) < if(file_exists(__DIR__ . DIRECTORY_SEPARATOR . str_replace("\\", DIRECTORY_SEPARATOR, $className) . ".php")< require_once __DIR__ . DIRECTORY_SEPARATOR . str_replace("\\", DIRECTORY_SEPARATOR, $className) . ".php"; >>); 

Class — How to check the existence of a namespace in, Add a comment. 6. As George Steel wrote, it is impossible to check for a namespace. This is because a namespace is not something that exists; only structures exist within namespaces. See below example: namespace Foo; class Bar < >var_dump (class_exists (‘Foo’)); // bool (false) var_dump (class_exists …

Php: Use a variable value to check class exists with ::class

The $name class is set to be included in a separate namespace using a factory method.

Php throws an error because it dislikes this.

Fatal error: Dynamic class names are not allowed in compile-time 

How can i get around this?

A while back, I recall hearing about the absence of «::class» in PHP during a web presentation on MVC or \ \ \ \ \ design\ patterns\ \ \ \ . I’m uncertain if it has been implemented in PHP > 7. Regardless, using «::class» is unnecessary. Instead, provide a fully qualified name (FQN) as a string when using class_exists. For instance:

$classFQN = "\myNamespaceName\mySubNamespaceName1\mySubNamespaceName2\myClassName"; if (class_exists($classFQN))

Observe the initial «\» (back-slash) which fully qualifies the name of \ \ \ \ \ namespaced\ class\ \ \ \ . For more information, refer to the «PSR-4: Autoloader» available at http://www.php-fig.org/psr/psr-4/.

function getClassInGlobal($name)< if(isset($GLOBALS[$name]))< if(is_object($GLOBALS[$name]))< $obj = $GLOBALS[$name]; return new $obj(); >else< return false; >; >else< return false; >; >; $Files = getClassInGlobal('myFilesClass'); if($Files)< echo '
'; print_r(get_class_methods($Files)); echo '
 
PHP — Check if global class exists inside namespace, How can you check if a global class exists with class_exists if you are inside the namespace of another class? For example: > Where class is a …
 
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PHP — Check if global class exists inside namespace
 
How can you check if a global class exists with class_exists if you are inside the namespace of another class? For example:
 
Where class is a global defined class.
 
Answers
 
You’ve had to screw up something in your other issues — most likely the class test is not declared in this scope (did you forget include?). I tested this thusly:
 
 > $nc = new ExampleClass(); $nc->testNamespace(); 
 
The results were expected: it prints out «1». So check your include paths.
 
function does_url_exists($url) < $ch = curl_init($url); curl_setopt($ch, CURLOPT_NOBODY, true); curl_exec($ch); $code = curl_getinfo($ch, CURLINFO_HTTP_CODE); if ($code == 200) < $status = true; >else < $status = false; >curl_close($ch); return $status; > 
 
In PHP 7.0 there will be anonymous classes. I don’t fully understand your question, but your create_class() function might look like this:
 
function create_class(string $key, array &$repository) < $obj = new class($key) < private $key; function __construct($key) < $this->key = $key; > >; $repository[$key] = $obj; return $obj; > 
 
This will instantiate an object with an anonymous class type and register it into the $repository . To get an object out you use the key you created it with: $repository[‘it.is.an.example’] .
 
I think you can implement rpc like interface, for one class. For other you can extend and use. http://en.wikipedia.org/wiki/Remote_procedure_call
 
No. If you often need quick direct lookup of values, you need to use array keys for them, which are lightning fast to lookup. For example:
 
// prepare once $indexed = array(); foreach ($array as $object) < $indexed[$object->id] = $object; > // lookup often if (isset($indexed[42])) < // object with id 42 exists. >
 
If you need to lookup objects by different keys, so you can’t really index them by one specific key, you need to look into different search strategies like binary searches.
 
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