先保存函数，再在函数头写/**+enter就行了

/** * @param $num1 * @param $num2 * @param $opt * @return float|int */function calc($num1, $num2, $opt){    switch ($opt) {        case '+':            $res = $num1 + $num2;            break;        case '-':            $res = $num1 - $num2;            break;        case '*':            $res = $num1 * $num2;            break;        case '/':            if ($num2 != 0) {                $res = $num1 / $num2;            } else {                exit('除数不能为0');            }            break;        case '%':            $res = $num1 % $num2;            break;    }    return $res;}echo "\n";echo calc(1, 2, '+');echo "\n";echo calc(1, 2, '/');echo "\n";echo calc(1, 2, '%');