Links

6. 流程控制

if-else

if condition
then
command1
command3
command2
fi
if condition
then
command1
...
else
commad1
...
fi

if-else-if

if condition
then
command1
commadn2
...
elif condition
then
commadm
..
else
...
fi

for 循环

for varname in item1 item2 ... itemN
do
command1
command2
...
commandN
done

while 循环

while condition
do
command
done

until 循环

until condition
do
command
done

case 多分支选择

case value in
p1)
command1
command2
;;
p2)
command1
command2
;;
esac
demo
echo '输入 1 到 4 之间的数字:'
echo '你输入的数字为:'
read aNum
case $aNum in
1) echo '你选择了 1'
;;
2) echo '你选择了 2'
;;
3) echo '你选择了 3'
;;
4) echo '你选择了 4'
;;
*) echo '你没有输入 1 到 4 之间的数字'
;;
esac

break

跳出后续所有的循环

continue

跳出当前循环