case语句 选择结构

case 语句：选择结构

case SWITCH in SWITCH要引用变量的值
value 1)
statement
...
;;
value 2)
statement
...
;;
* )
statement
...
;;
esac

用户从键盘传递参数，并确认给定的参数所属字符类型
#!/bin/bash
#
case $1 in
[0-9])
echo "A digit." ;;
[a-z])
echo "Lower." ;;
[A-Z])
echo "Upper." ;;
*)
echo "Special character." ;;
esac

[root@localhost ~]# vim case1
[root@localhost ~]# ./case1 2
A digit.
[root@localhost ~]# ./case1 a
Lower.
[root@localhost ~]# ./case1 A
Upper.
[root@localhost ~]# ./case1 $
Special character.

#!/bin/bash
#
case $1 in
'start')
echo "start server..."
;;
'stop')
echo "stop server..."
;;
'restart')
echo "restart server..."
;;
'status')
echo "running..."
;;
*)
echo "`basename $0` {start|stop|restart|status}"
;;
esac
[root@localhost ~]# vim service.sh
[root@localhost ~]# ./service.sh start
start server...
[root@localhost ~]# ./service.sh stop
stop server...
[root@localhost ~]# ./service.sh status
running...
[root@localhost ~]# ./service.sh restart
restart server...
[root@localhost ~]# ./service.sh run
service.sh {start|stop|restart|status}