Question

错误发生在第21行......

if [ $weight1 -gt $weight2 ];
    then echo "Weight 2 should be greater than Weight 1."
else
    if [ $weight1 -ge 20 ] && [ $weight1 -le 39 ];
        then echo "Weight 1 is bike."
    else 
        echo "Weight 1 is either bicycle, car, van or lorry."
    fi
fi

Answer 1

我没有看到问题，在我的测试then关键字适用于您的情况，无论如何在您的代码中注明了一些：

将then放在if运营商的行上：

if [ $weight1 -ge 20 ] && [ $weight1 -le 39 ]; then

将变量括在引号中：

if [ "$weight1" -ge 20 ] && [ "$weight1" -le 39 ]; then

我建议使用-a密钥，而不是两次拨打[ app：
```
if [ "$weight1" -ge 20 -a "$weight1" -le 39 ]; then
```

注意：错误Syntax error near unexpected token 'then'可能会在少数情况下上升：

在then案例之外指定if关键字时：

weight1=21
    then echo "Weight 1 is bike."
else
    echo "Weight 1 is either bicycle, car, van or lorry."
fi

两次指定then时：

if [ "$weight1" -ge 20 -a "$weight1" -le 39 ]; then
then echo "Weight 1 is bike."

当您将then置于不正确的位置时，例如，在else运算符之后：
```
else
then
    echo "Weight 1 is either bicycle, car, van or lorry."
fi
```

Answer 2

只是

chmod +x test.sh

第一行：添加#!/bin/bash

然后做：

./test.sh

它正在解决问题

Bash：意外令牌附近的语法错误`then'

2 个答案: