C＃正则表达式。 字符串后的可选匹配

Question

I have an input like this test1.test2.part01 which I want to strip away to test1.test2 . The only thing i know is that it will end with partxx and probably a dot before the partxx . However, it will not always be a apart. Another example of input might be testas1.tlp2.asd3.part10 which ofcourse should be stripped to testas1.tlp2.asd3 .

I've made all that, no problem. The problem is the dot at the end before partxx . My regex at the moment is:

(.*)\.?part\d{1,2}

But it will include the dot in the group. I do not want the dot to be in the group. The below works as I want it, given that the dot exists, but it will not always be there.

(.*)\.part\d{1,2}

How can I exclude the optional dot from the group?

Answer 1

Escape the dot

(.*)\.?part\d{1,2}

The way you have it, the dot is interpreted as meaning "any character" rather than a literal dot.

Alternatively,

s/\.part\d\d?$//;