试试oobash。

它是Bash 4的OO风格字符串库。它支持德语元音变音。它是用巴什语写的。

有许多函数可用：-base64Decode、-base64Encode、-acapital、-center、-charAt、concat、-concontains、-count、-endsWith、-equals、-equalsIgnoreCase、-reverse、-hashCode、-indexOf、-isAlnum、-isAlpha、-isAscii、-isDigit、-isEmpty、-isHexDigit、-isLowerCase、-isSpace、-isPrintable、-isUpperCase、-isVisible、-lastIndexOf、-length、-matches、-replaceAll、-replaceFirst、-startsWith，-substring、-swapCase、-toLowerCase、-toString、-toUpperCase、-trim和-zfill。

查看包含的示例：

[Desktop]$ String a testXccc
[Desktop]$ a.contains tX
true
[Desktop]$ a.contains XtX
false

oobash可在Sourceforge.net上获得。

字符串包含变量（兼容或不区分大小写）

由于这些Stack Overflow的答案主要讲述了Bash，我在这篇文章的底部发布了一个独立于大小写的Bash函数。。。

总之，有我的

兼容答案

由于已经有很多使用Bash特定功能的答案，因此有一种方法可以在功能较差的shell下工作，例如BusyBox：

[ -z "${string##*$reqsubstr*}" ]

在实践中，这可能会：

string='echo "My string"'
for reqsubstr in 'o "M' 'alt' 'str';do
  if [ -z "${string##*$reqsubstr*}" ] ;then
      echo "String '$string' contain substring: '$reqsubstr'."
    else
      echo "String '$string' don't contain substring: '$reqsubstr'."
    fi
  done

这是在Bash、Dash、KornShell（ksh）和ash（BusyBox）下测试的，结果总是：

String 'echo "My string"' contain substring: 'o "M'.
String 'echo "My string"' don't contain substring: 'alt'.
String 'echo "My string"' contain substring: 'str'.

集成到一个函数中

正如@EeroAaltonen所问，这里是相同演示的一个版本，在相同的外壳下测试：

myfunc() {
    reqsubstr="$1"
    shift
    string="$@"
    if [ -z "${string##*$reqsubstr*}" ] ;then
        echo "String '$string' contain substring: '$reqsubstr'.";
      else
        echo "String '$string' don't contain substring: '$reqsubstr'."
    fi
}

然后：

$ myfunc 'o "M' 'echo "My String"'
String 'echo "My String"' contain substring 'o "M'.

$ myfunc 'alt' 'echo "My String"'
String 'echo "My String"' don't contain substring 'alt'.

注意：必须转义或双引号和/或双引号：

$ myfunc 'o "M' echo "My String"
String 'echo My String' don't contain substring: 'o "M'.

$ myfunc 'o "M' echo \"My String\"
String 'echo "My String"' contain substring: 'o "M'.

简单的功能

这是在BusyBox、Dash和Bash下测试的：

stringContain() { [ -z "${2##*$1*}" ]; }

现在：

$ if stringContain 'o "M3' 'echo "My String"';then echo yes;else echo no;fi
no
$ if stringContain 'o "M' 'echo "My String"';then echo yes;else echo no;fi
yes

…或者，如果提交的字符串可能为空，如@Sjlver所指出的，则函数将变为：

stringContain() { [ -z "${2##*$1*}" ] && [ -z "$1" -o -n "$2" ]; }

或者正如Adrian Günter的评论所建议的，避免使用-o开关：

stringContain() { [ -z "${2##*$1*}" ] && { [ -z "$1" ] || [ -n "$2" ];};}

最终（简单）功能：

并反转测试以使其可能更快：

stringContain() { [ -z "$1" ] || { [ -z "${2##*$1*}" ] && [ -n "$2" ];};}

对于空字符串：

$ if stringContain '' ''; then echo yes; else echo no; fi
yes
$ if stringContain 'o "M' ''; then echo yes; else echo no; fi
no

独立于大小写（仅限Bash！）

对于不区分大小写的字符串测试，只需将每个字符串转换为小写：

stringContain() {
    local _lc=${2,,}
    [ -z "$1" ] || { [ -z "${_lc##*${1,,}*}" ] && [ -n "$2" ] ;} ;}

检查：

stringContain 'o "M3' 'echo "my string"' && echo yes || echo no
no
stringContain 'o "My' 'echo "my string"' && echo yes || echo no
yes
if stringContain '' ''; then echo yes; else echo no; fi
yes
if stringContain 'o "M' ''; then echo yes; else echo no; fi
no

我不确定是否使用if语句，但您可以使用case语句获得类似的效果：

case "$string" in 
  *foo*)
    # Do stuff
    ;;
esac

这里回答的问题的扩展如何判断POSIX sh中的字符串是否包含另一个字符串？：

此解决方案适用于特殊字符：

# contains(string, substring)
#
# Returns 0 if the specified string contains the specified substring,
# otherwise returns 1.
contains() {
    string="$1"
    substring="$2"

    if echo "$string" | $(type -p ggrep grep | head -1) -F -- "$substring" >/dev/null; then
        return 0    # $substring is in $string
    else
        return 1    # $substring is not in $string
    fi
}

contains "abcd" "e" || echo "abcd does not contain e"
contains "abcd" "ab" && echo "abcd contains ab"
contains "abcd" "bc" && echo "abcd contains bc"
contains "abcd" "cd" && echo "abcd contains cd"
contains "abcd" "abcd" && echo "abcd contains abcd"
contains "" "" && echo "empty string contains empty string"
contains "a" "" && echo "a contains empty string"
contains "" "a" || echo "empty string does not contain a"
contains "abcd efgh" "cd ef" && echo "abcd efgh contains cd ef"
contains "abcd efgh" " " && echo "abcd efgh contains a space"

contains "abcd [efg] hij" "[efg]" && echo "abcd [efg] hij contains [efg]"
contains "abcd [efg] hij" "[effg]" || echo "abcd [efg] hij does not contain [effg]"

contains "abcd *efg* hij" "*efg*" && echo "abcd *efg* hij contains *efg*"
contains "abcd *efg* hij" "d *efg* h" && echo "abcd *efg* hij contains d *efg* h"
contains "abcd *efg* hij" "*effg*" || echo "abcd *efg* hij does not contain *effg*"

我使用这个函数（一个不包括但很明显的依赖项）。它通过了以下测试。如果函数返回值>0，则找到字符串。你也可以很容易地返回1或0。

function str_instr {
   # Return position of ```str``` within ```string```.
   # >>> str_instr "str" "string"
   # str: String to search for.
   # string: String to search.
   typeset str string x
   # Behavior here is not the same in bash vs ksh unless we escape special characters.
   str="$(str_escape_special_characters "${1}")"
   string="${2}"
   x="${string%%$str*}"
   if [[ "${x}" != "${string}" ]]; then
      echo "${#x} + 1" | bc -l
   else
      echo 0
   fi
}

function test_str_instr {
   str_instr "(" "'foo@host (dev,web)'" | assert_eq 11
   str_instr ")" "'foo@host (dev,web)'" | assert_eq 19
   str_instr "[" "'foo@host [dev,web]'" | assert_eq 11
   str_instr "]" "'foo@host [dev,web]'" | assert_eq 19
   str_instr "a" "abc" | assert_eq 1
   str_instr "z" "abc" | assert_eq 0
   str_instr "Eggs" "Green Eggs And Ham" | assert_eq 7
   str_instr "a" "" | assert_eq 0
   str_instr "" "" | assert_eq 0
   str_instr " " "Green Eggs" | assert_eq 6
   str_instr " " " Green "  | assert_eq 1
}

正如Paul在绩效比较中提到的：

if echo "abcdefg" | grep -q "bcdef"; then
    echo "String contains is true."
else
    echo "String contains is not true."
fi

这是符合POSIX的，就像Marcus提供的答案中的“case“$string”一样，但它比case语句答案更容易阅读。还要注意，这将比使用case语句慢得多。正如保罗所指出的，不要在循环中使用它。