PHP object literal | 易学教程

问题

In PHP, I can specify array literals quite easily:

array(
    array("name" => "John", "hobby" => "hiking"),
    array("name" => "Jane", "hobby" => "dancing"),
    ...
)

But what if I want array of objects? How can I specify object literal in PHP? I.e. in javascript it would be:

[
    {name: "John", hobby: "hiking"},
    {name: "Jane", hobby: "dancing"}
]

回答1:

As BoltClock mentioned there is no object literal in PHP however you can do this by simply type casting the arrays to objects:

$testArray = array(
    (object)array("name" => "John", "hobby" => "hiking"),
    (object)array("name" => "Jane", "hobby" => "dancing")
);

echo "Person 1 Name: ".$testArray[0]->name;
echo "Person 2 Hobby: ".$testArray[1]->hobby;

回答2:

As of PHP 5.4 you can also use the short array syntax:

$json = [
    (object) ['name' => 'John', 'hobby' => 'hiking'],
    (object) ['name' => 'Jane', 'hobby' => 'dancing'],
];

回答3:

As others have noted, there is no object literal in PHP, but you can "fake" it by casting an array to an object.

With PHP 5.4, this is even more concise, because arrays can be declared with square brackets. For example:

$obj = (object)[
    "foo" => "bar",
    "bar" => "foo",
];

This would give you an object with "foo" and "bar" properties. However, I don't think this really provides much advantage over using associative arrays. It's just a syntax difference.

Consider embracing the uniqueness and "flavor" of all the languages you use. In JavaScript, object literals are all over the place. In PHP, associative arrays are functionally the same as JavaScript object literals, are easy to create, and are well understood by other PHP programmers. I think you're better off embracing this "flavor" than trying to make it feel like JavaScript's object literal syntax.

回答4:

Another way would be to use the __set_state() magic method:

$object = stdClass::__set_state (array (
    'height'   => -10924,
    'color'    => 'purple',
    'happy'    => false,
    'video-yt' => 'AgcnU74Ld8Q'
));

Some more on the __set_state() method, where is it coming from and how is it supposed to be used.

回答5:

Although casting as an (object) works fine on a single hierarchical level, it doesn't go deep. In other words, if we want objects at every level, we'd have to do something like:

$foods = (object)[
  "fruits" => (object)["apple" => 1, "banana" => 2, "cherry" => 3],
  "vegetables" => (object)["asparagus" => 4, "broccoli" => 5, "carrot" => 6]
];

However, instead of doing multiple casting as objects, we can wrap the whole thing in a json_encode and json_decode like this:

$foods = json_decode(json_encode([
  "fruits" => ["apple" => 1, "banana" => 2, "cherry" => 3],
  "vegetables" => ["asparagus" => 4, "broccoli" => 5, "carrot" => 6]
]));

That makes sure it's an object at the deepest level.

回答6:

My way of JavaScript-style object literals in PHP is as follows:

First I create an associative array like this:

$test = array(
  'name' => "test",
  'exists' => true
);

Then I easily make it an object like this:

$test = (object)$test;

Now you can test it:

echo gettype($test); // "object"
echo $test->name; // "test"

回答7:

In PHP, you have ro create an instance before you can use a class. Of course you can put the instances into an array later.

回答8:

If you're wanting to define modules in the object literal pattern "like JavaScript", you could do something like this:

$object = (object) [
    'config' => (object) [
        'username' => 'Rob Bennet',
        'email' => 'rob@madebyhoundstooth.com'
    ],

    'hello' => function() use(&$object) {
        return "Hello " . $object->config->username . ". ";
    },

    'emailDisplay' => function() use(&$object) {
        return "Your email address is " . $object->config->email;
    },

    'init' => function($options) use(&$object) {
        $object->config = $options;
        $doUsername = $object->hello;
        $doEmail = $object->emailDisplay;
        return $doUsername() . $doEmail();
    }
];

$sayMyInfo = $object->init;

echo $sayMyInfo((object) [
    'username' => 'Logan',
        'email' => 'wolverine@xmen.com'
]);

In this type of modular scenario, I usually opt for the facade pattern, I just like writing my calls thusly:

Module::action()->item;

Post::get()->title;

Neither of these patterns make it easy (or even possible sometimes) for testing. But this is just proof of concept. Technically, "no" there is no Object Literal in PHP, but if you're used to JavaScript syntax (which I am more so than PHP), you can fake it and do this. As you can see, it's a lot messier in PHP than in JavaScript.

回答9:

If the json_decode(json_encode( $array )) isn't good for you, then you can use some similar functions like these. Which one is faster, I don't know.

function deep_cast_object( $o ){
  return deep_cast_object_ref( $o );
}

function deep_cast_object_ref( & $o ){

  if( is_array( $o ))
    $o = (object)$o;

  if( is_object( $o ))
    foreach( $o as & $v )
      deep_cast_object_ref( $v );

  return $o;
}

$obj = deep_cast_object(array(
  'Fractal' => array(
    'of'    => array(
      'bad' => 'design',
    ),
  ),
));

var_dump( $obj );

来源：https://stackoverflow.com/questions/9644870/php-object-literal

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php

object

literals

object-literal