Hướng dẫn get property php
Class member variables are called properties. They may be referred to using other terms such as fields, but for the purposes of this reference properties will be used. They are defined by using at least one modifier (such as Visibility, Static
Keyword, or, as of PHP 8.1.0, readonly), optionally (except for
Within class methods non-static properties may be accessed by using The pseudo-variable $this is available inside any class method when that method is called from within an object context. $this is the value of the calling object. Example #1 Property declarations
$var8 = <<<'EOD'
Type declarationsAs of PHP 7.4.0, property definitions can include Type declarations, with the exception of callable. Example #2 Example of typed properties
__construct(int $id, ?string $name) The above example will output: Typed properties must be initialized before accessing, otherwise an Error is thrown. Example #3 Accessing properties
setNumberOfSides(int $numberOfSides): void The above example will output: string(8) "triangle" int(3) string(6) "circle" Fatal error: Uncaught Error: Typed property Shape::$numberOfSides must not be accessed before initialization Readonly properties As of PHP 8.1.0, a property can be declared with the Example #4 Example of readonly properties
__construct(string $prop) {
A readonly property can only be initialized once, and only from the scope where it has been declared. Any other assignment or modification of the property will result in an Error exception. Example #5 Illegal initialization of readonly properties
Modifications are not necessarily plain assignments, all of the following will also result in an Error exception:
However, readonly properties do not preclude interior mutability. Objects (or resources) stored in readonly properties may still be modified internally:
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toArray()
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__isset($name) Ashley Dambra ¶ 8 years ago
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