Access static object property through variable name

问题

I know its possible to access an object property/method using a variable as its name

ex.:

$propName = 'something';
$something = $object->$propName;

Is it possible to do the same w/ constants or static properties?

I've tried:

$constName = 'MY_CONST';

MyCLass::{$constName};

and

$obj::{$constName};

But nothing seems to work and I couldn't find it anywhere.

回答1:

Use: Class::$$constName, this is similar to normal variable variables.

Demo:

<?php    
class MyClass {
    public static $var = 'A';
}
$name = 'var';
echo MyClass::$$name; // echoes 'A'

Constants can be access with the constant function:

constant('MyClass::'.$constantName)

回答2:

This works for me:

<?php
class Test {
  public static $nombre = "pepe";

  public function __construct() {
    return self;
  }
}

$varName = "nombre";
echo Test::${$varName};

回答3:

You can use the constant function:

constant('bar::'. $const);
constant("$obj::". $const); //note the double quote 

来源：https://stackoverflow.com/questions/22495096/access-static-object-property-through-variable-name