Question

我正在做一个简单的计算器，可以选择是否继续。但是当我尝试乘法运算时，我在控制台中出错：

calculator.sh: line 17: [: too many arguments
calculator.sh: line 22: [: too many arguments
calculator.sh: line 27: [: too many arguments
calculator.sh: line 32: [: too many arguments

这基本上意味着我的所有操作都有此错误，但当我使用它们时，情况并非如此，它们会正常运行。我在堆栈溢出中搜索相似之处，但示例不同。我用斜线逃脱了*，但我认为它与角色＃34; *＆＃34;进行比较时会出错。为了到达if语句的主体。这是代码：

#!/bin/bash
choice="Y"
while [ $choice == "Y" ]
do
echo -n "Enter first value:"
read firstvar
echo -n "Enter second value:"
read secondvar
echo -n "Enter last value:"
read compvar
echo -n "Enter operation:"
read ops
counter=0
result=0
while [ $result != $compvar ]
do
if [ $ops == "+" ]
then result=$((firstvar+secondvar))
echo "Do you want to continue ? Y/N"
read choice
break
elif [ $ops == "-" ]
then result=$((firstvar-secondvar))
echo "Do you want to continue ? Y/N"
read choice
break
elif [ $ops == "*" ]
then result=$((firstvar\*secondvar))
echo "Do you want to continue ? Y/N"
read choice
break
elif [ $ops == "/" ]
then result=$((firstvar/secondvar))
echo "Do you want to continue ? Y/N"
read choice
break
else
echo "Input valid operation !!!"
echo "Do you want to continue ? Y/N"
read choice
break
fi
counter=$((counter+1))
done
done

Answer 1

问题可能不是因为脚本中的"*"，而是因为$ops变量中的星号。

您应该对变量进行双引号以避免将globbing应用于它们;像这样重写你的测试：

elif [ "$ops" = "*" ]

这是一个非常有用的resource for checking your shell scripts。

Answer 2

首先，请查看Charles Duffy的评论WRT“==”vs“=”进行字符串测试。将$ ops的出现更改为“$ {ops}”。删除result = $（（firstvar * secondvar））中的转义。我冒昧地重新编写了脚本。希望这会有所帮助。

#!/bin/bash
choice="Y"
while [ $choice = "Y" ]
do
  echo -n "Enter first value:"
  read firstvar
  echo -n "Enter second value:"
  read secondvar
  echo -n "Enter last value:"
  read compvar
  echo -n "Enter operation:"
  read ops
  counter=0
  result=0
  while [ $result != $compvar ]
  do
    if [ "${ops}" = "+" ]; then
      result=$((firstvar+secondvar))
      echo "Do you want to continue ? Y/N"
      read choice
      break
    elif [ "${ops}" = "-" ]; then
      result=$((firstvar-secondvar))
      echo "Do you want to continue ? Y/N"
      read choice
      break
    elif [ "${ops}" = "*" ]; then
      result=$((firstvar*secondvar))
      echo "Do you want to continue ? Y/N"
      read choice
      break
    elif [ "${ops}" = "/" ]; then
      result=$((firstvar/secondvar))
      echo "Do you want to continue ? Y/N"
      read choice
      break
    else
      echo "Input valid operation !!!"
      echo "Do you want to continue ? Y/N"
      read choice
      break
    fi
    counter=$((counter+1))
  done
done

shell脚本*操作提供了太多参数

2 个答案: