我知道我可以很容易地在bash中获得这样的定位参数:
$0或$1
我希望能够使用这样的标志选项来指定每个参数的使用:
mysql -u user -h host
获得-u参数值和-h参数值的最佳方法是通过标志而不是通过位置?
我知道我可以很容易地在bash中获得这样的定位参数:
$0或$1
我希望能够使用这样的标志选项来指定每个参数的使用:
mysql -u user -h host
获得-u参数值和-h参数值的最佳方法是通过标志而不是通过位置?
当前回答
另一种选择是使用类似下面例子的东西,它允许你使用长——image或短的-i标签,还允许编译-i="example.jpg"或单独的-i example.jpg方法来传递参数。
# declaring a couple of associative arrays
declare -A arguments=();
declare -A variables=();
# declaring an index integer
declare -i index=1;
# any variables you want to use here
# on the left left side is argument label or key (entered at the command line along with it's value)
# on the right side is the variable name the value of these arguments should be mapped to.
# (the examples above show how these are being passed into this script)
variables["-gu"]="git_user";
variables["--git-user"]="git_user";
variables["-gb"]="git_branch";
variables["--git-branch"]="git_branch";
variables["-dbr"]="db_fqdn";
variables["--db-redirect"]="db_fqdn";
variables["-e"]="environment";
variables["--environment"]="environment";
# $@ here represents all arguments passed in
for i in "$@"
do
arguments[$index]=$i;
prev_index="$(expr $index - 1)";
# this if block does something akin to "where $i contains ="
# "%=*" here strips out everything from the = to the end of the argument leaving only the label
if [[ $i == *"="* ]]
then argument_label=${i%=*}
else argument_label=${arguments[$prev_index]}
fi
# this if block only evaluates to true if the argument label exists in the variables array
if [[ -n ${variables[$argument_label]} ]]
then
# dynamically creating variables names using declare
# "#$argument_label=" here strips out the label leaving only the value
if [[ $i == *"="* ]]
then declare ${variables[$argument_label]}=${i#$argument_label=}
else declare ${variables[$argument_label]}=${arguments[$index]}
fi
fi
index=index+1;
done;
# then you could simply use the variables like so:
echo "$git_user";
其他回答
这是我常用的成语:
while test $# -gt 0; do
case "$1" in
-h|--help)
echo "$package - attempt to capture frames"
echo " "
echo "$package [options] application [arguments]"
echo " "
echo "options:"
echo "-h, --help show brief help"
echo "-a, --action=ACTION specify an action to use"
echo "-o, --output-dir=DIR specify a directory to store output in"
exit 0
;;
-a)
shift
if test $# -gt 0; then
export PROCESS=$1
else
echo "no process specified"
exit 1
fi
shift
;;
--action*)
export PROCESS=`echo $1 | sed -e 's/^[^=]*=//g'`
shift
;;
-o)
shift
if test $# -gt 0; then
export OUTPUT=$1
else
echo "no output dir specified"
exit 1
fi
shift
;;
--output-dir*)
export OUTPUT=`echo $1 | sed -e 's/^[^=]*=//g'`
shift
;;
*)
break
;;
esac
done
要点如下:
$#是参数的个数 While循环查看提供的所有参数,在case语句中匹配它们的值 Shift移走了第一个。您可以在case语句中多次移位以获取多个值。
#!/bin/bash
if getopts "n:" arg; then
echo "Welcome $OPTARG"
fi
保存为sample.sh 试着跑步
sh sample.sh -n John
在你的终端。
Getopt是你的朋友。举个简单的例子:
function f () {
TEMP=`getopt --long -o "u:h:" "$@"`
eval set -- "$TEMP"
while true ; do
case "$1" in
-u )
user=$2
shift 2
;;
-h )
host=$2
shift 2
;;
*)
break
;;
esac
done;
echo "user = $user, host = $host"
}
f -u myself -h some_host
在您的/usr/bin目录中应该有各种示例。
我建议一个简单的TLDR:;非初始化的例子。
创建一个名为greeting .sh的bash脚本
#!/bin/bash
while getopts "n:" arg; do
case $arg in
n) Name=$OPTARG;;
esac
done
echo "Hello $Name!"
然后可以在执行脚本时传递一个可选参数-n。
执行脚本如下:
$ bash greeter.sh -n 'Bob'
输出
$ Hello Bob!
笔记
如果你想使用多个参数:
扩展while getops "n:" arg: do使用更多参数,例如 而getops“n:o:p:”arg: do 用额外的变量赋值扩展大小写开关。如o) Option=$OPTARG和p) Parameter=$OPTARG
要使脚本可执行:
chmod u+x greeter.sh
另一种选择是使用类似下面例子的东西,它允许你使用长——image或短的-i标签,还允许编译-i="example.jpg"或单独的-i example.jpg方法来传递参数。
# declaring a couple of associative arrays
declare -A arguments=();
declare -A variables=();
# declaring an index integer
declare -i index=1;
# any variables you want to use here
# on the left left side is argument label or key (entered at the command line along with it's value)
# on the right side is the variable name the value of these arguments should be mapped to.
# (the examples above show how these are being passed into this script)
variables["-gu"]="git_user";
variables["--git-user"]="git_user";
variables["-gb"]="git_branch";
variables["--git-branch"]="git_branch";
variables["-dbr"]="db_fqdn";
variables["--db-redirect"]="db_fqdn";
variables["-e"]="environment";
variables["--environment"]="environment";
# $@ here represents all arguments passed in
for i in "$@"
do
arguments[$index]=$i;
prev_index="$(expr $index - 1)";
# this if block does something akin to "where $i contains ="
# "%=*" here strips out everything from the = to the end of the argument leaving only the label
if [[ $i == *"="* ]]
then argument_label=${i%=*}
else argument_label=${arguments[$prev_index]}
fi
# this if block only evaluates to true if the argument label exists in the variables array
if [[ -n ${variables[$argument_label]} ]]
then
# dynamically creating variables names using declare
# "#$argument_label=" here strips out the label leaving only the value
if [[ $i == *"="* ]]
then declare ${variables[$argument_label]}=${i#$argument_label=}
else declare ${variables[$argument_label]}=${arguments[$index]}
fi
fi
index=index+1;
done;
# then you could simply use the variables like so:
echo "$git_user";