在PHP中有条件地使用特征

Question

I want to use a trait in a class, only if a condition is satisfied. For example:

trait T
{
}
class A
{
    if ($condition) {
        use T;
    }
}

I know I can't use if directly in class. So, I'm looking for a way to use traits conditionally similar to the above. Is it possible?

Answer 1

You can create a class with use T which extends the class without use T. And then in your code where you use the class do an if and instanciate the one or the other class.

<?php

trait T {
}

class A {
}

class B extends A {
    use T;
}

// In an other part of code
$obj = null;

if($condition) {
    $obj = new B();
} else {
    $obj = new A();
}

/* EOF */