What is data binding in php

What is binding in PHP and MySQL? And what are the uses of it?

Question: Can i bind method of class Foo to class Bar? PHP doesn’t know it was created from class method and therefore allows to bind any .

What is binding in PHP and MySQL? And what are the uses of it?

I usually use mysql_query() to get data from mysql database. But some people use binding to set results. What is the different between then? In my view both give the same result. But i feel binding is bit complicated. Can anyone please what are the advantages of using bind? Thank you.

Data binding offers enhanced protection from SQL injection attacks (sometimes referred to as SQLIA). SQL injections are malicious attempts to gain access to your database for reasons outside intended use. Use your imagination here. As a result, using mysql_connect is a really bad idea and the library is deprecated as of PHP 5.5.0. For a more comprehensive overview, see this article.

Binding is not as complicated as it seems if you break down a SQL query, it can very easily explained.

Take the following code in the old mysql library as an example:

mysql_query( "INSERT INTO users (username, password, user_data) VALUES ('derek_jeter', 'password', 'additional_data')" ); 

This code is vulnerable to SQLIA. With a library such as PDO, you just need to add an extra step to avoid the issue entirely. To achieve the same result in a safer library, you just need to translate the above code into the following:

$db->prepare("INSERT INTO users (username, password, user_data) VALUES (:username, :password, :additional_data)"; $db->execute( array("username" => "derek_jeter", "password" => "password", "additional_data" => "additional_data") ); 

Binding sends the data to be inserted into MySQL separately from the query, and understands how to parse it for insertion without risking safety of the database. With the execute function, you just pass the array with keys corresponding to the placeholder data you defined in the prepare function.

Note: I’m using the word «function», but since the PDO library is actually an object you manipulate, the functions contained in the PDO class are technically referred to as «methods».

There’s a bit more you’ll need to do before you can just run queries in PDO (such as instantiating the PDO connection and class), but I’ll refer you to the docs which explain everything in great detail.

Also, here’s a tutorial I used when I first started using PDO and MySQLi.

Php 7 — PHP binding method to another class, We have specifically prohibited this in PHP 7.1. Previously, it was possible to perform this kind of rebinding (of course, using ReflectionMethod::getClosure() rather than Closure::fromCallable(), which was only added in PHP 7.1), but this is no longer allowed.

PHP binding method to another class

Can i bind method of class Foo to class Bar? And why the code below throws a warning «Cannot bind method Foo::say() to object of class Bar»? With function instead of method code works fine.

P.S. I know about extending) it is not practical question, just want to know is it real to bind non-static method to another class

class Foo < public $text = 'Hello World!'; public function say() < echo $this->text; > > class Bar < public $text = 'Bye World!'; public function __call($name, $arguments) < $test = Closure::fromCallable(array(new Foo, 'say')); $res = Closure::bind($test, $this); return $res(); >> $bar = new Bar(); $bar->say(); 

 function say()< echo $this->text; > class Bar < public $text = 'Bye World!'; public function __call($name, $arguments) < $test = Closure::fromCallable('say'); $res = Closure::bind($test, $this); return $res(); >> $bar = new Bar(); $bar->say(); 

This is currently not supported. If you want to bind a closure to a new object, it must not be a fake closure, or the new object must be compatible with the old one (source).

So, what is a fake closure : A fake closure is a closure created from Closure::fromCallable .

This means, you have two options to fix your problem:

1. Bar must be compatible with the type of Foo — so just make Bar extend from Foo , if possible.
2. Use unbound functions, like annonymous, static or functions outside of classes.

It is not supported by PHP. However in PHP 7.0 it was kinda possible. Consider this example:

class Foo < private $baz = 1; public function baz() < var_dump('Foo'); var_dump($this->baz); > > class Bar < public $baz = 2; public function baz() < var_dump('Bar'); var_dump($this->baz); > > $fooClass = new ReflectionClass('Foo'); $method = $fooClass->getMethod('baz'); $foo = new Foo; $bar = new Bar; $closure = $method->getClosure($foo); $closure2 = $closure->bindTo($bar); $closure2(); 

The output of foregoing code is:

And this means method Foo::baz was called on object $bar and has accessed its $baz property rather than Foo::$baz .

Also, please note that Bar::$baz is public property. If it was private, php would throw Fatal error cannot access private property. This could’ve be fixed up by changing the scope of closure $closure->bindTo($bar, $bar); , however doing this was already prohibited in php7.0 and would lead to a following warning: Cannot rebind scope of closure created by ReflectionFunctionAbstract::getClosure() .

There’s workaround however , which will work for latest versions of php. Laravel created a splendid package called laravel/serializable-closure . What it does is simple — it reads source code of closure in order to serialize it and be able to unserialize it later with all necessary context.

So basically the functionality of unserialized closure remains the same, however it is different from PHP’s perspective. PHP doesn’t know it was created from class method and therefore allows to bind any $this .

Final variant will look like this:

$callback = [$foo, 'baz']; $closure = unserialize( serialize(new SerializableClosure(Closure::fromCallable($callback))) )->getClosure(); $closure->call($bar); 

Please, note that serialization and unserialization are expensive operations, so do not use provided solution unless there’s no other solution.

PHP Form Handling, When the user fills out the form above and clicks the submit button, the form data is sent for processing to a PHP file named «welcome.php». The form data is sent with the HTTP POST method. To display the submitted data you could simply echo all the variables. The «welcome.php» looks like this: The same result could also …

What exactly are late static bindings in PHP?

What exactly are late static binding s in PHP?

You definitely need to read late static bindings in the PHP manual. However, I’ll try to give you a quick summary.

Basically, it boils down to the fact that the self keyword does not follow the same rules of inheritance. self always resolves to the class in which it is used. This means that if you make a method in a parent class and call it from a child class, self will not reference the child as you might expect.

Late static binding introduces a new use for the static keyword, which addresses this particular shortcoming. When you use static , it represents the class where you first use it, ie. it ‘binds’ to the runtime class.

Those are the two basic concepts behind it. The way self , parent and static operate when static is in play can be subtle, so rather than go in to more detail, I’d strongly recommend that you study the manual page examples. Once you understand the basics of each keyword, the examples are quite necessary to see what kind of results you’re going to get.

As of PHP 5.3.0, PHP implements a feature called late static binding which can be used to reference the called class in the context of static inheritance .

Late static binding tries to solve that limitation by introducing a keyword that references the class that was initially called at runtime. . It was decided not to introduce a new keyword, but rather use static that was already reserved.

 private static function getName() < return 'Car'; >> class Toyota extends Car < public static function getName() < return 'Toyota'; >> echo Car::run(); // Output: Car echo Toyota::run(); // Output: Toyota ?> 

Late static bindings work by storing the class named in the last «non-forwarding call». In case of static method calls, this is the class explicitly named (usually the one on the left of the :: operator); in case of non-static method calls, it is the class of the object. A «forwarding call» is a static one that is introduced by self:: , parent:: , static:: , or, if going up in the class hierarchy, forward_static_call() . The function get_called_class() can be used to retrieve a string with the name of the called class and static:: introduces its scope.

There is not very obvious behavior:

The following code produces ‘alphabeta’.

class alpha < function classname()< return __CLASS__; >function selfname() < return self::classname(); >function staticname() < return static::classname(); >> class beta extends alpha < function classname()< return __CLASS__; >> $beta = new beta(); echo $beta->selfname(); // Output: alpha echo $beta->staticname(); // Output: beta 

However, if we remove the declaration of the classname function from the beta class, we get ‘alphaalpha’ as the result.

I’m quoting from the book: «PHP Master write cutting-edge code».

Late static binding was a feature introduced with php 5.3. It allows us to inherit static methods from a parent class, and to reference the child class being called.

This means you can have an abstract class with static methods, and reference the child class’s concrete implementations by using the static::method() notation instead of the self::method().

Feel free to take a look at the official php documentation as well: http://php.net/manual/en/language.oop5.late-static-bindings.php

The clearest way to explain Late Static Binding is with a practicle example. I’m using it in a Template method pattern. See below.

abstract class AbstractTemplate < public const AWESOME_LIST = ['']; public function someFunction(): void < $awesomeList = $this->getAwesomeList(); // OUTPUT: ['harry','henk','john']; var_dump($awesomeList); > /** * This function gets static constants from CHILD classes */ public function getAwesomeList(): array < return static::AWESOME_LIST; >> class ConcreteTemplate extends AbstractTemplate < public const AWESOME_LIST = ['harry','henk','john']; public function someFunction(): void < parent::someFunction(); >> $concreteTemplate = new ConcreteTemplate(); $concreteTemplate->someFunction(); 

Notice the static keyword in method getAwesomeList . Let’s change a bit now:

public function getAwesomeList(): array

The output of the var_dump at someFunction would be:

array (size=1) 0 => string '' (length=0) 

The static keyword is used in a Singleton design pattern. See link: https://refactoring.guru/ design-patterns/singleton /php/example

Can’t bind in php against Active Directory LDAP over SSL?, As of right now, TLS binding is disabled on our domain controllers, I just want to use AD SSL binding over 636 (instead of TLS over 389). We are using PHP 5.6.30 on IIS 6.1 on a Server 2008 R2 serverWe have our migration target built which is Server 2016 on IIS 10 and PHP 7.2 and we’re seeing the same …

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Binding in PHP

Understanding binding in PHP is essential for anyone that wants to use this unique language. Late Static Binding (LSB) is the combination of Late binding and Static binding, two different concepts.

Static?

You make static calls when you don’t need any object creation. You can read this post if you need more details :

Understanding PHP static

jmau111⚡⚡⚡ ・ Mar 5 ’20 ・ 3 min read

It’s not rare to use static calls, even when a class inherits from its parent class. You may need some features that won’t vary.

Static binding

Sometimes, people refer to static binding with another term: early binding. Static binding happens when you use the scope resolution operator :: . When inheriting from a mother class in your child class, there’s a counter-intuitive behavior (maybe not ^^):

 class MotherClass  protected static $cat = "generation A"; public static function displayCat()  echo self::$cat; > > class ChildClass extends MotherClass  protected static $cat = "generation B"; > ChildClass::displayCat();// displays "generation A" 

As the displayCat() method is defined in the parent class, you’ll get the parent stuff even if you call it with the child class. PHP resolves it using the class in which the method belongs.

Late binding

Sometimes, people refer to late binding with another term: dynamic binding. Unlike early binding (static binding), PHP will bind things at runtime. It needs an object creation :

 class MotherClass  protected $cat = "generation A"; public function displayCat()  echo $this->cat; > > class ChildClass extends MotherClass  protected $cat = "generation B"; > $child = new ChildClass(); $child->displayCat();//displays "generation B" 

Late static binding

If you want to redefine static stuff (~ override output) in the child class, use the keyword static . The PHP interpreter will leave it for runtime. It’s like a pending status:

 class MotherClass  protected static $cat = "generation A"; public static function displayCat()  echo static::$cat; > > class ChildClass extends MotherClass  protected static $cat = "generation B"; > ChildClass::displayCat();// displays "generation B" 

Wrap up

I hope you know more about binding in PHP, especially late static binding, thanks to this short article. This technique has been available since PHP 5.3. It makes the use of static methods and variables less risky for inheritance thanks to a simple keyword.

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