我怎样才能称呼静态php变量？

Question

i want to know how to insert : self::$tag between <> , thanks

i tried <{self::$tag}> but it does not function .

<?php 
class model {
    public static $tag = "p" ;

    private static function surround($xx){
        return "<self::$tag>".$xx." </self::$tag>" ;
    }  //here is the problem    

    public static function label($xx){
        return self::surround("<label>".$xx."</label>") ;
    }
}
?>

Answer 1

You are close. Only the string concatenation is wrong. Try this:

return "<".self::$tag.">".$xx." </".self::$tag.">" ;