我想暂停shell脚本中的输入,并提示用户进行选择。标准的是、否或取消类型问题。如何在典型的bash提示符中完成此操作?
当前回答
要获得像inputbox这样的漂亮ncurses,请使用如下命令对话框:
#!/bin/bash
if (dialog --title "Message" --yesno "Want to do something risky?" 6 25)
# message box will have the size 25x6 characters
then
echo "Let's do something risky"
# do something risky
else
echo "Let's stay boring"
fi
默认情况下,对话框包至少在SUSE Linux上安装。看起来像:
其他回答
echo "Please enter some input: "
read input_variable
echo "You entered: $input_variable"
yn() {
if [[ 'y' == `read -s -n 1 -p "[y/n]: " Y; echo $Y` ]];
then eval $1;
else eval $2;
fi }
yn 'echo yes' 'echo no'
yn 'echo absent no function works too!'
可以在POSIX shell中处理区域设置感知的“是/否选项”;通过使用LC_MESSAGES语言环境类别的条目,witch提供了与输入匹配的现成RegEx模式,以及本地化Yes No的字符串。
#!/usr/bin/env sh
# Getting LC_MESSAGES values into variables
# shellcheck disable=SC2046 # Intended IFS splitting
IFS='
' set -- $(locale LC_MESSAGES)
yesexpr="$1"
noexpr="$2"
yesstr="$3"
nostr="$4"
messages_codeset="$5" # unused here, but kept as documentation
# Display Yes / No ? prompt into locale
echo "$yesstr / $nostr ?"
# Read answer
read -r yn
# Test answer
case "$yn" in
# match only work with the character class from the expression
${yesexpr##^}) echo "answer $yesstr" ;;
${noexpr##^}) echo "answer $nostr" ;;
esac
编辑:正如@Urhixidur在评论中提到的:
不幸的是,POSIX只指定了前两个(yeexpr和noexpr)。在Ubuntu 16上,yestr和nostr为空。
参见:https://www.ee.ryerson.ca/~courses/ele709/susv4/xrat/V_4_xbd_chap07.html#tag_21_07_03_06
LC_消息yestr和nostr语言环境关键字以及yesstr和nostr语言信息项以前用于匹配用户的肯定和否定响应。在POSIX.1-2008中,yeexpr、noexpr、yesexpr和noexpr扩展正则表达式已取代它们。应用程序应该使用通用的基于语言环境的消息传递工具来发出包含所需响应示例的提示消息。
或者使用Bash方式的区域设置:
#!/usr/bin/env bash
IFS=$'\n' read -r -d '' yesexpr noexpr _ < <(locale LC_MESSAGES)
printf -v yes_or_no_regex "(%s)|(%s)" "$yesexpr" "$noexpr"
printf -v prompt $"Please answer Yes (%s) or No (%s): " "$yesexpr" "$noexpr"
declare -- answer=;
until [[ "$answer" =~ $yes_or_no_regex ]]; do
read -rp "$prompt" answer
done
if [[ -n "${BASH_REMATCH[1]}" ]]; then
echo $"You answered: Yes"
else
echo $"No, was your answer."
fi
使用语言环境提供的regexp来匹配答案。
要翻译剩余的消息,请使用bash--dump po string scriptname输出po字符串以进行本地化:
#: scriptname:8
msgid "Please answer Yes (%s) or No (%s): "
msgstr ""
#: scriptname:17
msgid "You answered: Yes"
msgstr ""
#: scriptname:19
msgid "No, was your answer."
msgstr ""
inquire () {
echo -n "$1 [y/n]? "
read answer
finish="-1"
while [ "$finish" = '-1' ]
do
finish="1"
if [ "$answer" = '' ];
then
answer=""
else
case $answer in
y | Y | yes | YES ) answer="y";;
n | N | no | NO ) answer="n";;
*) finish="-1";
echo -n 'Invalid response -- please reenter:';
read answer;;
esac
fi
done
}
... other stuff
inquire "Install now?"
...
针对其他人:
您不需要在BASH4中指定大小写,只需使用',,'使var小写即可。此外,我强烈不喜欢将代码放在读取块内,获取结果并在读取块IMO外处理它。还包括一个“q”表示退出IMO。最后,为什么键入“yes”只需使用-n1并按y。
示例:用户可以按y/n和q退出。
ans=''
while true; do
read -p "So is MikeQ the greatest or what (y/n/q) ?" -n1 ans
case ${ans,,} in
y|n|q) break;;
*) echo "Answer y for yes / n for no or q for quit.";;
esac
done
echo -e "\nAnswer = $ans"
if [[ "${ans,,}" == "q" ]] ; then
echo "OK Quitting, we will assume that he is"
exit 0
fi
if [[ "${ans,,}" == "y" ]] ; then
echo "MikeQ is the greatest!!"
else
echo "No? MikeQ is not the greatest?"
fi