regex - Regular expression and number with last two letters in C#

Question

I have code that I want to get out of the string. The problem I have is that the texts can be of different lengths ranging from 8 characters to the 18 character, but some also have "SE" at the end.

enter code here
String String1 = "Hello 213123123SE world";
String String2 = "Hello 888888888 World"

and then i have now i can only take numbers in all length

 string regexp = @"[^d$]";

(i will output see out here)OutPut:

"213123123SE" "888888888"

I want both to have only numbers and numbers with "SE" at the end

Answer 1

If I have interpreted your question correctly, try this: [d]{8,18}(SE)?

(You can try it out here: http://gskinner.com/RegExr/ unfortunately the Share Link feature isn't working)