saves one function call compares to intval($value) and settype($value, 'int').
而且 (int)$value 已經足夠干凈了，所以我更喜歡這種方式.
And (int)$value is clean enough, so I prefer this way.
When you need to use intval($value) 是當你需要使用指定的基數進行轉換時(默認為基數 10).intval 接受第二個參數作為轉換的基礎.
When you need to use intval($value) is that when you need to use the specified base for the conversion (the default is base 10). intval accepts a second parameter for the base for the conversion.
