PHP:如何使用另一个类中的参数实例化一个类 [英] PHP: How to instantiate a class with arguments from within another class

问题描述

我处于一种需要用另一个类的实例中的参数实例化一个类的情况. 这是原型:

I am in a situations where i need to instantiate a class with arguments from within an instance of another class. Here is the prototype:

//test.php

class test
{
    function __construct($a, $b, $c)
    {
        echo $a . '<br />';
        echo $b . '<br />';
        echo $c . '<br />';
    }
}

现在，我需要使用下面的类的 cls 函数实例化上面的类:

Now, i need to instantiate above class using below class's cls function:

class myclass
{
function cls($file_name, $args = array())
{
    include $file_name . ".php";

    if (isset($args))
    {
        // this is where the problem might be, i need to pass as many arguments as test class has.
        $class_instance = new $file_name($args);
    }
    else
    {
        $class_instance = new $file_name();
    }

    return $class_instance;
}
}

现在，当我尝试向其传递参数时尝试创建测试类的实例时:

Now when i try to create an instance of test class while passing arguments to it:

$myclass = new myclass;
$test = $myclass->cls('test', array('a1', 'b2', 'c3'));

它给出了错误: 缺少论点1和2；仅传递第一个参数.

It gives error: Missing argument 1 and 2; only first argument is passed.

如果我实例化一个在其构造函数中没有任何参数的类，这将很好地工作.

This works fine if i instantiate a class which has no arguments in it's constructor function.

对于有经验的PHP开发人员而言，上述问题不应该太大.请帮忙.

For experienced PHP developers, above should not be much of a problem. Please help.

谢谢

推荐答案

您需要反射 http ://php.net/manual/en/class.reflectionclass.php

if(count($args) == 0)
   $obj = new $className;
else {
   $r = new ReflectionClass($className);
   $obj = $r->newInstanceArgs($args);
}

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