111 lines
1.5 KiB
Markdown
111 lines
1.5 KiB
Markdown
---
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title: PHP
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category: PHP
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layout: 2017/sheet
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prism_languages: [php]
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---
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### Hello world
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#### hello.php
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```php
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<?php
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function greetMe($name): string
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{
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return "Hello, " . $name . "!";
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}
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$message = greetMe($name);
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echo $message;
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```
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All PHP files start with `<?php`.
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See: [PHP tags](https://php.net/manual/en/language.basic-syntax.phptags.php)
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### Objects
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```php
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<?php
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$fruitsArray = array(
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"apple" => 20,
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"banana" => 30
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);
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echo $fruitsArray['banana'];
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```
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Or cast as object
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```php
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<?php
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$fruitsObject = (object) $fruits;
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echo $fruitsObject->banana;
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```
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### Inspecting objects
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```php
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<?php
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var_dump($object)
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```
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Prints the contents of a variable for inspection.
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See: [var_dump](https://php.net/var_dump)
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### Classes
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```php
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class Person
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{
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public $name = '';
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}
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$person = new Person();
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$person->name = 'bob';
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echo $person->name;
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```
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### Getters and setters
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```php
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class Person
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{
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private $name = '';
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public function getName(): string
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{
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return $this->name;
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}
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public function setName(string $name)
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{
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$this->name = $name;
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return $this;
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}
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}
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$person = new Person();
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$person->setName('bob');
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echo $person->getName();
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```
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### isset vs empty
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```php
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$options = [
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'key' => 'value',
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'blank' => '',
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'nothing' => null,
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];
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var_dump(isset($options['key']), empty($options['key'])); // true, false
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var_dump(isset($options['blank']), empty($options['blank'])); // true, true
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var_dump(isset($options['nothing']), empty($options['nothing'])); // false, true
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```
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