如何在PHP中完成__constructor后自动调用方法？

我写了一个名为Task的小抽象类.我喜欢让每个任务逻辑类扩展它.

在我的抽象类“Task”中,我喜欢调用在每个类中定义的已使用的已定义方法“execute”.

我尝试使用魔术方法__call,但它不起作用.

如果您在我的方法中注意到我正在回显一条从未在屏幕上打印的消息.

这是我的抽象Task类

<?php

namespace App\Modules\Surveys\Tasks;

use App\Modules\Surveys\Tasks\Support\Traits\HtmlHelper;

abstract class Task
{
    /*
    |
    | This task base class provides a central location to place any logic that
    | is shared across all of your tasks. 
    |
    */

    use HtmlHelper;


    /**
     * checks wether a get method execute exists and calls it
     *
     * @param string $name
     * @param array $args optional
     * @return mixed
     */
    public function __call($name, $args = [])
    {

        echo 'Attempt to execute task';

        if (method_exists($this, 'execute')) {

            return call_user_func_array('execute', $args);

        } else {

            throw new \Exception('execute method does does not exists in your task! ' . get_class($this) );

        }
    }
}


?>

这是一个逻辑类

<?php 

namespace App\Modules\Surveys\Tasks\Interviews;

use App\Modules\Surveys\Tasks\Task;

use App\Modules\Surveys\Models\SurveyInterview;

use Exception;


class ResumeInterview extends Task
{

    protected $surveyId;

    protected $callId;

    protected $myInterview;

    /**
     * Create a new task instance.
     *
     * @return void
     */
    public function __construct($surveyId, $callId)
    {

        $this->surveyId = intval($surveyId);

        $this->callId = intval($callId);
    }


    /**
     * Resume existing interview if one exists using the giving $surveyId and $callId
     *
     * @return void
     */
    protected function execute()
    {
        //find the current interview if one exits
        $myInterview = SurveyInterview::surveyAndCall($this->surveyId, $this->callId)->first();

        $this->setInterview($myInterview);

        if( $this->wasResumed() ){
            //At this point existing interview was found

            if($myInterview->status != 'Pending'){
                //At this point the interview is completed and should not be conducted
                throw new Exception('This interview can not not be retaken. It\'s current status is "' . $myInterview->status . '"');
            }

        }


    }

    /**
     * Return the current interview
     * 
     * @return App\Models\Survey\SurveyInterview
     */
    public function getInterview()
    {
        return $this->myInterview;
    }

    /**
     * It checks whether ot the the interview was resumed
     * 
     * @return boolean
     */
    public function wasResumed()
    {
        return $this->getInterview() ? true : false;
    }

    /**
     * It sets the interview
     * 
     * @param Illuminate\Support\Collection $myInterview
     * @param  void
     */
    protected function setInterview($myInterview)
    {
        $this->myInterview = $myInterview;
    }
}

如果存在,我将如何自动调用execute方法,否则抛出异常？

解决方法:

我会这样：

abstract class Task {
    [...]

    public function __construct() {
        $this->execute();
    }

    protected function execute() {
        throw new Exception('NOT IMPLEMENTED');
    }

    [...]
}

class ResumeInterview extends Task {
    protected $surveyId;
    protected $callId;
    protected $myInterview;

    public function __construct($surveyId, $callId) {
        $this->surveyId = intval($surveyId);
        $this->callId = intval($callId);
        parent::__construct();
    }

    protected function execute() { [...] }
}

只需在基类构造函数中调用execute().

编辑：注意调用parent :: __ construct();只有子类实现自己的构造函数时才需要,否则不需要.

标签：php,class,call,magic-methods
来源： https://codeday.me/bug/20190829/1761804.html