How can I make this javascript code to php? [closed]

int key = 6;
       String text ="Hellow Word!";
        char [] chars = 
        text.toCharArray();
        System.out.println(text);
        for (char c : chars){
            c += key;
            System.out.print(c);
        }
Sample output:

Hellow Word!

Nkrru}&]uxj

I tried to convert this code to a php one but i find it very hard.