我想编写一个shell脚本，它读取字符串直到两次引入字符串

Question

我是shell脚本的新手，但我尝试了以下内容：

#!/bin/sh

declare -a s
read string1
s[0] = string1

while ((a<=2))
do
    read string2
    for i in "${s[@]}"
    do
         if $i=string2 
         then
             a=3
             exit 1
         fi
    done
    s[@+1]=string2
done

它不起作用，我甚至不确定我是否需要使用数组。任何帮助都会很棒。

Answer 1

只是一些错误。更正如下

declare -a s
read -p "enter a value: " string1
s[0]=$string1      # must not have spaces around `=`
                   # must use `$` to get the *value* of a variable

while true         # infinite loop
do
    read -p "enter a value: " string2
    for i in "${s[@]}"
    do
         if [[ "$i" = "$string2" ]]   # how to test string equality
         then
             break    # break the loop
         fi
    done
    s+=("$string2")      # append a value to the array
done