我想要一个没有外部依赖关系、有严格bash支持(-u)的东西，而且我需要它能在较旧的bash版本上工作。这个函数处理各种类型的参数:

短bool (-h) 短选项(-i "image.jpg") 长boos(——救命) = options(——file="filename.ext") 空格选项(——file "filename.ext") 连接的bool (-hvm)

只需在脚本顶部插入以下内容:

# Check if a list of params contains a specific param
# usage: if _param_variant "h|?|help p|path f|file long-thing t|test-thing" "file" ; then ...
# the global variable $key is updated to the long notation (last entry in the pipe delineated list, if applicable)
_param_variant() {
  for param in $1 ; do
    local variants=${param//\|/ }
    for variant in $variants ; do
      if [[ "$variant" = "$2" ]] ; then
        # Update the key to match the long version
        local arr=(${param//\|/ })
        let last=${#arr[@]}-1
        key="${arr[$last]}"
        return 0
      fi
    done
  done
  return 1
}

# Get input parameters in short or long notation, with no dependencies beyond bash
# usage:
#     # First, set your defaults
#     param_help=false
#     param_path="."
#     param_file=false
#     param_image=false
#     param_image_lossy=true
#     # Define allowed parameters
#     allowed_params="h|?|help p|path f|file i|image image-lossy"
#     # Get parameters from the arguments provided
#     _get_params $*
#
# Parameters will be converted into safe variable names like:
#     param_help,
#     param_path,
#     param_file,
#     param_image,
#     param_image_lossy
#
# Parameters without a value like "-h" or "--help" will be treated as
# boolean, and will be set as param_help=true
#
# Parameters can accept values in the various typical ways:
#     -i "path/goes/here"
#     --image "path/goes/here"
#     --image="path/goes/here"
#     --image=path/goes/here
# These would all result in effectively the same thing:
#     param_image="path/goes/here"
#
# Concatinated short parameters (boolean) are also supported
#     -vhm is the same as -v -h -m
_get_params(){

  local param_pair
  local key
  local value
  local shift_count

  while : ; do
    # Ensure we have a valid param. Allows this to work even in -u mode.
    if [[ $# == 0 || -z $1 ]] ; then
      break
    fi

    # Split the argument if it contains "="
    param_pair=(${1//=/ })
    # Remove preceeding dashes
    key="${param_pair[0]#--}"

    # Check for concatinated boolean short parameters.
    local nodash="${key#-}"
    local breakout=false
    if [[ "$nodash" != "$key" && ${#nodash} -gt 1 ]]; then
      # Extrapolate multiple boolean keys in single dash notation. ie. "-vmh" should translate to: "-v -m -h"
      local short_param_count=${#nodash}
      let new_arg_count=$#+$short_param_count-1
      local new_args=""
      # $str_pos is the current position in the short param string $nodash
      for (( str_pos=0; str_pos<new_arg_count; str_pos++ )); do
        # The first character becomes the current key
        if [ $str_pos -eq 0 ] ; then
          key="${nodash:$str_pos:1}"
          breakout=true
        fi
        # $arg_pos is the current position in the constructed arguments list
        let arg_pos=$str_pos+1
        if [ $arg_pos -gt $short_param_count ] ; then
          # handle other arguments
          let orignal_arg_number=$arg_pos-$short_param_count+1
          local new_arg="${!orignal_arg_number}"
        else
          # break out our one argument into new ones
          local new_arg="-${nodash:$str_pos:1}"
        fi
        new_args="$new_args \"$new_arg\""
      done
      # remove the preceding space and set the new arguments
      eval set -- "${new_args# }"
    fi
    if ! $breakout ; then
      key="$nodash"
    fi

    # By default we expect to shift one argument at a time
    shift_count=1
    if [ "${#param_pair[@]}" -gt "1" ] ; then
      # This is a param with equals notation
      value="${param_pair[1]}"
    else
      # This is either a boolean param and there is no value,
      # or the value is the next command line argument
      # Assume the value is a boolean true, unless the next argument is found to be a value.
      value=true
      if [[ $# -gt 1 && -n "$2" ]]; then
        local nodash="${2#-}"
        if [ "$nodash" = "$2" ]; then
          # The next argument has NO preceding dash so it is a value
          value="$2"
          shift_count=2
        fi
      fi
    fi

    # Check that the param being passed is one of the allowed params
    if _param_variant "$allowed_params" "$key" ; then
      # --key-name will now become param_key_name
      eval param_${key//-/_}="$value"
    else
      printf 'WARNING: Unknown option (ignored): %s\n' "$1" >&2
    fi
    shift $shift_count
  done
}

像这样使用它:

# Assign defaults for parameters
param_help=false
param_path=$(pwd)
param_file=false
param_image=true
param_image_lossy=true
param_image_lossy_quality=85

# Define the params we will allow
allowed_params="h|?|help p|path f|file i|image image-lossy image-lossy-quality"

# Get the params from arguments provided
_get_params $*

长选项可以被内置的标准getopts作为- " option "的"参数"解析。

这是可移植的本地POSIX shell -不需要外部程序或bashisms。

本指南将长选项作为-选项的参数实现，因此——alpha被getopts视为参数alpha为-，而——bravo=foo被参数bravo=foo视为-。true实参通过shell参数展开获取，更新$OPT和$OPTARG。

在本例中，-b和-c(以及它们的长形式——bravo和——charlie)具有强制实参。长选项的参数出现在等号之后，例如——bravo=foo(长选项的空格分隔符很难实现，参见下文)。

因为它使用了内置的getopts，所以这个解决方案支持像cmd——bravo=foo -ac FILE这样的用法(它组合了选项-a和-c，并将长选项与标准选项交织在一起)，而这里的大多数其他答案要么很难做到，要么无法做到这一点。

die() { echo "$*" >&2; exit 2; }  # complain to STDERR and exit with error
needs_arg() { if [ -z "$OPTARG" ]; then die "No arg for --$OPT option"; fi; }

while getopts ab:c:-: OPT; do
  # support long options: https://stackoverflow.com/a/28466267/519360
  if [ "$OPT" = "-" ]; then   # long option: reformulate OPT and OPTARG
    OPT="${OPTARG%%=*}"       # extract long option name
    OPTARG="${OPTARG#$OPT}"   # extract long option argument (may be empty)
    OPTARG="${OPTARG#=}"      # if long option argument, remove assigning `=`
  fi
  case "$OPT" in
    a | alpha )    alpha=true ;;
    b | bravo )    needs_arg; bravo="$OPTARG" ;;
    c | charlie )  needs_arg; charlie="$OPTARG" ;;
    ??* )          die "Illegal option --$OPT" ;;  # bad long option
    ? )            exit 2 ;;  # bad short option (error reported via getopts)
  esac
done
shift $((OPTIND-1)) # remove parsed options and args from $@ list

When the option is a dash (-), it is a long option. getopts will have parsed the actual long option into $OPTARG, e.g. --bravo=foo originally sets OPT='-' and OPTARG='bravo=foo'. The if stanza sets $OPT to the contents of $OPTARG before the first equals sign (bravo in our example) and then removes that from the beginning of $OPTARG (yielding =foo in this step, or an empty string if there is no =). Finally, we strip the argument's leading =. At this point, $OPT is either a short option (one character) or a long option (2+ characters).

The case then matches either short or long options (the pipe, |, indicates that "or" operation. A long-only option like delta ) delta=true ;; doesn't need a pipe). For short options, getopts automatically complains about options and missing arguments, so we have to replicate those manually using the needs_arg function, which fatally exits when $OPTARG is empty. The ??* condition will match any remaining long option (? matches a single character and * matches zero or more, so ??* matches 2+ characters), allowing us to issue the "Illegal option" error before exiting.

与正常的gnu风格的长选项一样，提供——将停止解析，因此- -- --bravo=4将把$alpha设置为true，但$bravo将保持不变，$1将-bravo=4。我不能说我建议用前导破折号来命名文件，但这是表示它们不是选项的方法。

小错误:如果有人给出了一个无效的单字符长选项(它也不是一个短选项)，这将退出一个错误，但没有消息(这个实现假设它是一个短选项)。您可以在case之前的条件中使用一个额外的变量来跟踪它，然后在最后的case条件中测试它，但我认为这是一个太麻烦的角落情况。

大写变量名:一般情况下，建议保留全大写变量供系统使用。我将$OPT保留为全大写，以与$OPTARG保持一致，但这确实打破了这种约定。我认为这很合适，因为这是系统应该做的事情，它应该是安全的;我还没有听说过任何使用这个变量名的标准。

要抱怨长选项的非预期实参:用翻转测试模拟needs_argg来抱怨一个非预期实参:

no_arg() { if [ -n "$OPTARG" ]; then die "No arg allowed for --$OPT option"; fi; }

要接受带空格分隔参数的长选项:您可以用eval "ARG_B=\"\$$OPTIND\""(或使用bash的间接展开，ARG_B="${!OPTIND}")拉入下一个参数，然后增加$OPTIND，正如这个答案的旧版本所指出的那样，但它不可靠;getopts可以过早地终止，假设参数超出了它的作用域，并且一些实现不太适合手动操作$OPTIND。

Getopts“可以用来”解析长选项，只要你不希望它们有参数……

以下是如何:

$ cat > longopt
while getopts 'e:-:' OPT; do
  case $OPT in
    e) echo echo: $OPTARG;;
    -) #long option
       case $OPTARG in
         long-option) echo long option;;
         *) echo long option: $OPTARG;;
       esac;;
  esac
done

$ bash longopt -e asd --long-option --long1 --long2 -e test
echo: asd
long option
long option: long1
long option: long2
echo: test

如果尝试使用OPTIND获取长选项的参数，getopts将把它作为第一个不可选的位置参数，并停止解析任何其他参数。 在这种情况下，您最好使用简单的case语句手动处理它。

这将“总是”工作:

$ cat >longopt2
while (($#)); do
    OPT=$1
    shift
    case $OPT in
        --*) case ${OPT:2} in
            long1) echo long1 option;;
            complex) echo comples with argument $1; shift;;
        esac;;

        -*) case ${OPT:1} in
            a) echo short option a;;
            b) echo short option b with parameter $1; shift;;
        esac;;
    esac
done


$ bash longopt2 --complex abc -a --long -b test
comples with argument abc
short option a
short option b with parameter test

尽管它不像getopts那么灵活，而且你必须在用例实例中自己做很多错误检查代码……

但这是一种选择。

我是这样解决的:

# A string with command options
options=$@

# An array with all the arguments
arguments=($options)

# Loop index
index=0

for argument in $options
  do
    # Incrementing index
    index=`expr $index + 1`

    # The conditions
    case $argument in
      -a) echo "key $argument value ${arguments[index]}" ;;
      -abc) echo "key $argument value ${arguments[index]}" ;;
    esac
  done

exit;

我是不是太笨了?Getopt和getopts太让人困惑了。

如果这就是您想要调用脚本的方式

myscript.sh --input1 "ABC" --input2 "PQR" --input2 "XYZ"

然后，您可以使用getopt和——longoptions来实现这个最简单的方法

试试这个，希望对你有用

# Read command line options
ARGUMENT_LIST=(
    "input1"
    "input2"
    "input3"
)



# read arguments
opts=$(getopt \
    --longoptions "$(printf "%s:," "${ARGUMENT_LIST[@]}")" \
    --name "$(basename "$0")" \
    --options "" \
    -- "$@"
)


echo $opts

eval set --$opts

while true; do
    case "$1" in
    --input1)  
        shift
        empId=$1
        ;;
    --input2)  
        shift
        fromDate=$1
        ;;
    --input3)  
        shift
        toDate=$1
        ;;
      --)
        shift
        break
        ;;
    esac
    shift
done

一个简单的DIY，只获得长名称的参数:

Use:

$ ./test-args.sh --a1 a1 --a2 "a 2" --a3 --a4= --a5=a5 --a6="a 6"
a1 = "a1"
a2 = "a 2"
a3 = "TRUE"
a4 = ""
a5 = "a5"
a6 = "a 6"
a7 = ""

脚本:

#!/bin/bash

function main() {
    ARGS=`getArgs "$@"`

    a1=`echo "$ARGS" | getNamedArg a1`
    a2=`echo "$ARGS" | getNamedArg a2`
    a3=`echo "$ARGS" | getNamedArg a3`
    a4=`echo "$ARGS" | getNamedArg a4`
    a5=`echo "$ARGS" | getNamedArg a5`
    a6=`echo "$ARGS" | getNamedArg a6`
    a7=`echo "$ARGS" | getNamedArg a7`

    echo "a1 = \"$a1\""
    echo "a2 = \"$a2\""
    echo "a3 = \"$a3\""
    echo "a4 = \"$a4\""
    echo "a5 = \"$a5\""
    echo "a6 = \"$a6\""
    echo "a7 = \"$a7\""

    exit 0
}


function getArgs() {
    for arg in "$@"; do
        echo "$arg"
    done
}


function getNamedArg() {
    ARG_NAME=$1

    sed --regexp-extended --quiet --expression="
        s/^--$ARG_NAME=(.*)\$/\1/p  # Get arguments in format '--arg=value': [s]ubstitute '--arg=value' by 'value', and [p]rint
        /^--$ARG_NAME\$/ {          # Get arguments in format '--arg value' ou '--arg'
            n                       # - [n]ext, because in this format, if value exists, it will be the next argument
            /^--/! p                # - If next doesn't starts with '--', it is the value of the actual argument
            /^--/ {                 # - If next do starts with '--', it is the next argument and the actual argument is a boolean one
                # Then just repla[c]ed by TRUE
                c TRUE
            }
        }
    "
}


main "$@"