借鉴Dennis Williamson的答案，下面的解决方案结合了数组、shell-safe引号和正则表达式，以避免需要:遍历循环;使用管道或其他子过程;或者使用非bash实用程序。

declare -a array=('hello, stack' one 'two words' words last)
printf -v array_str -- ',,%q' "${array[@]}"

if [[ "${array_str},," =~ ,,words,, ]]
then
   echo 'Matches'
else
   echo "Doesn't match"
fi

上面的代码通过使用Bash正则表达式来匹配数组内容的字符串化版本。有六个重要的步骤来确保正则表达式匹配不会被数组中的值的巧妙组合所欺骗:

Construct the comparison string by using Bash's built-in printf shell-quoting, %q. Shell-quoting will ensure that special characters become "shell-safe" by being escaped with backslash \. Choose a special character to serve as a value delimiter. The delimiter HAS to be one of the special characters that will become escaped when using %q; that's the only way to guarantee that values within the array can't be constructed in clever ways to fool the regular expression match. I choose comma , because that character is the safest when eval'd or misused in an otherwise unexpected way. Combine all array elements into a single string, using two instances of the special character to serve as delimiter. Using comma as an example, I used ,,%q as the argument to printf. This is important because two instances of the special character can only appear next to each other when they appear as the delimiter; all other instances of the special character will be escaped. Append two trailing instances of the delimiter to the string, to allow matches against the last element of the array. Thus, instead of comparing against ${array_str}, compare against ${array_str},,. If the target string you're searching for is supplied by a user variable, you must escape all instances of the special character with a backslash. Otherwise, the regular expression match becomes vulnerable to being fooled by cleverly-crafted array elements. Perform a Bash regular expression match against the string.

别胡闹了!使您的解决方案简单、干净和可重用。

这些函数负责索引数组和关联数组。可以通过将搜索算法从线性搜索升级为二进制搜索(用于大型数据集)来改进它们。

##
# Determines if a value exists in an array.
###
function hasArrayValue ()
{
    local -r needle="{$1:?}"
    local -nr haystack="{$2:?}"  # Where you pass by reference to get the entire array in one argument.

    # Linear search. Upgrade to binary search for large datasets.
    for value in "${haystack[@]}"; do
        if [[ "$value" == "$needle" ]]; then
            return 0
        fi
    done

    return 1
}

##
# Determines if a value exists in an associative array / map.
###
function hasMapValue ()
{
    local -r needle="{$1:?}"
    local -nr haystack="{$2:?}"

    # Linear search. Upgrade to binary search for large datasets.
    for value in "${haystack[@]}"; do
        if [[ $value == $needle ]]; then
            return 0
        fi
    done

    return 1
}

是的，同样的逻辑，但在处理bash时，如果函数的名称可以让您知道迭代的对象(或不迭代的对象)，则可能(可能)有用。

使用grep和printf

在新行上格式化每个数组成员，然后grep这些行。

if printf '%s\n' "${array[@]}" | grep -x -q "search string"; then echo true; else echo false; fi

$ array=("word", "two words")
$ if printf '%s\n' "${array[@]}" | grep -x -q "two words"; then echo true; else echo false; fi
true

注意，这对delimeter和空格没有问题。

我通常只使用:

inarray=$(echo ${haystack[@]} | grep -o "needle" | wc -w)

非零值表示找到了匹配。

．.． 实际上，为了解决它不能与needle1和needle2工作的问题，如果你只想要一个精确匹配，没有更多，没有更少，只需在-o后面添加一个w标志，用于整个单词匹配:

inarray=$(echo ${haystack[@]} | grep -ow "needle" | wc -w)

考虑到:

array=("something to search for" "a string" "test2000")
elem="a string"

然后简单检查一下:

if c=$'\x1E' && p="${c}${elem} ${c}" && [[ ! "${array[@]/#/${c}} ${c}" =~ $p ]]; then
  echo "$elem exists in array"
fi

在哪里

c is element separator
p is regex pattern

(单独分配p，而不是直接在[[]]中使用表达式的原因是为了保持bash 4的兼容性)

a=(b c d)

if printf '%s\0' "${a[@]}" | grep -Fqxz c
then
  echo 'array “a” contains value “c”'
fi

如果你喜欢，你可以使用相同的长选项:

--fixed-strings --quiet --line-regexp --null-data