PHP：使用环境变量作为对本地常量的引用

Question

My code:

const T = 'test';
const B = 'boat';

$const_var = getenv('FOO');

In my VirtualHost section, I have:

SetEnv FOO T

Obviously $const_var evaluates to the character T .

What I want to do is to be able to use the value of local const T, by using the value of the environment variable as a reference. Is there a way to do that?

Answer 1

You can use the constant() function to resolve the value indirectly.

 print constant($_ENV["FOO"]);

Or in your case $const_var as parameter.