用正则表达式替换字符串中首次出现的“，”

Question

I have a issue with regex pattern. It replace not only "," but also all characters that are before.

I would like to replace first occurrence of the "," to ".":

"1,,000.23" -> "1.,000.23"

This pattern I am using now :

^(.*?),

Result that I receive is :

"1,,000.23" -> ".,000.23"

Expected result :

"1,,000.23" -> "1.,000.23"

Answer 1

Maybe you could use ^([^,]+), and replace with $1.

This will capture from the beginning of the string ^ not a comma in a group ([^,]+) and then match a comma ,

Answer 2

Use ^(.*?), and replace it with $1. . This means:

group as less as possible things from line start till first , into group 1
then match a `,` 
and replace it with the captured text of group 1 `$1` and a dot `.`

See: https://regexr.com/3kjdq

Answer 3

Copy the capture group to the result. Replace

^(.*?),

with

$1