PHP中substr()函数的解析(附代码详解)

substr ( string $string , int $start , int $length = ? )

"; echo substr('php.cn is all right', 1, 3); echo "
"; echo substr('php.cn is all right', 0, 4); echo "
"; echo substr('php.cn is all right', 0, 8); ?>

输出： hp.cn is all right hp. php. php.cn i

"; echo substr("php.cn is all right", -2); echo "
"; echo substr("php.cn is all right", -3, 1); ?>

输出： t ht g

"; echo substr("php.cn is all right",2, -1); echo "
"; echo substr("php.cn is all right",4, 4); echo "
"; echo substr("php.cn is all right",-3, -1); ?>

输出：php.cn is all righ p.cn is all righ cn i gh