bsp;  我们打开cmd，运行route print ，来查看一下当前的路由表，如下：
    Active Routes:
    Network Destination      Netmask          Gateway                Interface          Metric
    0.0.0.0                         0.0.0.0               192.168.0.1       192.168.5.20       20
    127.0.0.0                     255.0.0.0            127.0.0.1           127.0.0.1              1
    192.168.0.0                 255.255.248.0     192.168.5.20      192.168.5.20       20
    192.168.5.20               255.255.255.255  127.0.0.1           127.0.0.1             20
    192.168.5.255              255.255.255.255 192.168.5.20      192.168.5.20       20
    224.0.0.0                     240.0.0.0            192.168.5.20      192.168.5.20       20
    255.255.255.255          255.255.255.255  192.168.5.20     192.168.5.20         1
    Default Gatew