Bash子串删除

Question

我有以下模式的字符串：<SOMETHING_1>{<JSON>}<SOMETHING_2>

我想保留<JSON>并删除<SOMETHING_X>块。我试图通过删除子字符串来实现它，而不是获取

{x:1,action:PLAYING,name:John,description:Some description rSxv9HiATMuQ4wgoV2CGxw}

我一直在

{x:1,action:PLAYING,name:John,description:Some}

因为说明字段中的空格会切断子字符串。

关于改变什么的任何想法？

CODE：

string="000{x:1,action:PLAYING,name:John,description:Some description rSxv9HiATMuQ4wgoV2CGxw}401"
string=$1
string=$(echo "${string#*{}")
string=$(echo "${string%}*}")
string={$string}
echo $string

Answer 1

如果我们接受字符串的直接赋值，原始代码就可以正常工作 - 尽管以下内容更为明确：

string="000{x:1,action:PLAYING,name:John,description:Some description rSxv9HiATMuQ4wgoV2CGxw}401"
string='{'"${string#*"{"}"  # trim content up to and including the first {, and replace it
string="${string%'}'*}"'}'  # trim the last } and all after, and replace it again
printf '%s\n' "$string"

......正确发出：

{x:1,action:PLAYING,name:John,description:Some description rSxv9HiATMuQ4wgoV2CGxw}

我猜测字符串是在未加引号的命令行上传递的，因此被分成多个参数。如果引用命令行参数以防止调用shell（./yourscript "$string"而不是./yourscript $string）进行字符串拆分，则可以避免此问题。

Answer 2

使用sed：

string="000{x:1,action:PLAYING,name:John,description:Some description rSxv9HiATMuQ4wgoV2CGxw}401"
sed 's/.*\({.*}\).*/\1/g' <<<$string

输出：

{x:1,action:PLAYING,name:John,description:Some description rSxv9HiATMuQ4wgoV2CGxw}

Answer 3

你去......

string="000{x:1,action:PLAYING,name:John,description:Some description rSxv9HiATMuQ4wgoV2CGxw}401"
echo "original: ${string}"
string="${string#*\{}"
string="${string%\}*}"
echo "final: {${string}}"

顺便说一句，JSON键应该用双引号括起来。