Linux Gvim shell break和continue命令

#break和continue命令：循环过程中，有时需要在未达到循环结束条件时强制跳出循环
#break：允许跳出所有循环（终止执行后面的所有循环）

while :        #死循环写法#
do
    echo -n " Input a number between 1 to 5 : "
    read aNum
    case ${aNum} in
    1|2|3|4|5) 
        echo " Your number is ${aNum}"
        ;;
    *) 
        echo " You do not select a number betwwen 1 to 5 , game over ! " 
        break
        ;;
    esac
done

#循环嵌套，break可以跟一个参数，表示跳出第几层循环
#例：如果var1=2并且var2=0,跳出循环

for var1 in 1 2 3
do
    for var2 in 0 5 
    do
        if [ ${var1} -eq 2 -a ${var2} -eq 0 ]
        then 
            break 2
        else
            echo " ${var1} ${var2} "
        fi
    done
done

#continue命令：不会跳出所有循环，仅仅跳出当前循环
#运行代码发现，输入的不是1-5的数字，循环也不会被终止。echo " game over " 永远不被执行

while :
do
    echo " Input a number between 1 to 5 "
    read aNum
    case ${aNum} in
    1|2|3|4|5)
        echo " Your number is ${aNum} "
        ;;
    *)
        echo " you do not select a number between 1 to 5 ! "
        continue
        echo " game over "
        ;;
    esac
done

#寻找偶数

numbers="1 2 3 4 5 6"
for NUM in ${numbers}
do
    Q=` expr ${NUM} % 2 `
    if [ ${Q} -eq 0 ]
    then
        echo " Number is an even number "
        continue
    fi
    echo " Found odd number "
done