Why should the variables defined in the parameter list be called using func_get_arg in the function? Wouldn't it be more convenient to call them directly?

Question

function demo3($str3)
{
   $str3 = func_get_arg(0);
   return $str3;
}

与

function demo3($str3)

{

   return $str3;
}

Answer 1

You need to use callbacks under special conditions. Don’t worry about this. Just know that there is such a callback method.