doufei3152 2016-05-03 08:06
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PHP覆盖单个实例的功能

In javascript i know it is possible to simply override a class-method of a single instance but I am not quite sure how this is managable in PHP. Here is my first idea:

class Test {
    public $var = "placeholder";
    public function testFunc() {
        echo "test";
    }
}

$a = new Test();

$a->testFunc = function() {
    $this->var = "overridden";
};

My second attempt was with anonymous function calls which unfortunately kills the object scope...

class Test {
    public $var = "placeholder";
    public $testFunc = null;
    public function callAnonymTestFunc() {
        $this->testFunc();
    }
}

$a = new Test();

$a->testFunc = function() {
    //here the object scope is gone... $this->var is not recognized anymore
    $this->var = "overridden";
};

$a->callAnonymTestFunc();
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2条回答 默认 最新

  • duanpen9294 2016-05-03 17:15
    关注

    In order to fully understand what you are trying to achieve here, your desired PHP version should be known first, PHP 7 is more ideal for OOP approaches than any previous version.

    If the binding of your anonymous function is the problem, you can bind the scope of a function as of PHP >= 5.4 to an instance, e.g.

    $a->testFunc = Closure::bind(function() {
        // here the object scope was gone...
        $this->var = "overridden";
    }, $a);
    

    As of PHP >= 7 you can call bindTo immediately on the created Closure

    $a->testFunc = (function() {
        // here the object scope was gone...
        $this->var = "overridden";
    })->bindTo($a);
    

    Though your approach of what you are trying to achieve is beyond my imagination. Maybe you should try to clarify your goal and I'll workout all possible solutions.

    本回答被题主选为最佳回答 , 对您是否有帮助呢?
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