42 lines
748 B
Bash
42 lines
748 B
Bash
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#!/usr/bin/env bash
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calc(){
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PS3="choose the oper: "
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select oper in + - \* / # 生成操作符选择菜单
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do
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echo -n "enter first num: " && read x # 读取输入参数
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echo -n "enter second num: " && read y # 读取输入参数
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exec
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case ${oper} in
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"+")
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return $((${x} + ${y}))
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;;
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"-")
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return $((${x} - ${y}))
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;;
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"*")
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return $((${x} * ${y}))
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;;
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"/")
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return $((${x} / ${y}))
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;;
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*)
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echo "${oper} is not support!"
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return 0
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;;
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esac
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break
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done
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}
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calc
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echo "the result is: $?" # $? 获取 calc 函数返回值
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# $ ./function-demo.sh
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# 1) +
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# 2) -
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# 3) *
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# 4) /
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# choose the oper: 3
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# enter first num: 10
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# enter second num: 10
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# the result is: 100
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