模式匹配：case
========================================================

一、case 语法结构
case 变量 in
模式1)
命令序列1
;;
模式2)
命令序列2
;;
模式3)
命令序列3
;;
*)

无匹配后命令序列

esac
========================================================

#!/bin/sh
#Jeson made it
echo ‘Input a number between 1 to 4′
echo ‘Your number is:\c’
read aNum
case $aNum in
    1)  echo ‘You select 1′
    ;;
    2)  echo ‘You select 2′
    ;;
    3)  echo ‘You select 3′
    ;;
    4)  echo ‘You select 4′
    ;;
    *)  echo ‘You do not select a number between 1 to 4′
    ;;
esac