Regex 如何使用正则表达式替换子字符串值？

例如，我在一个文件中有几行，每行都是一个字符串，如下所示：

{"a":"53124647,44398061,44398058","b":"hello","c":"ha"}
{"b":"99","a":"44398049,44398031,44398028,10007072315,9569405558,10007072318","c":"ha"}
...

如果将每一行视为json对象，那么每一行中键

“a”

的值长度是灵活的，那么如何使用

sed

和

正则表达式

来替换键对

“a”

及其值与

“a”：“10”

$ echo '{"a":"53124647,44398061,44398058","b":"hello","c":"ha"}' | sed 's@"a":"[^"]*"@"a":"10"@'
{"a":"10","b":"hello","c":"ha"}

$ echo '{"a":"53124647,44398061,44398058","b":"hello","c":"ha"}
{"b":"99","a":"44398049,44398031,44398028,10007072315,9569405558,10007072318","c":"ha"}' | sed 's/"a":"[^"]*"/"a":"10"/g'
{"a":"10","b":"hello","c":"ha"}
{"b":"99","a":"10","c":"ha"}