Extracting parts of a string using Regex

Question

I have several strings that look like the following:

+H124005992014011/1527399999999I05Z

+H7039700000001/$99999999I051

+K122005962050171/120911234C117

I need each section to be split into its own variable. To do this i thought Regex would be the best way to go.

here are the rules for splitting.

• The first char must be the '+'
• The second section must have an alpha char followed by three digits. i.e. H124, H703, K122
• The third section is a set of alphanumeric chars (1 to 13 chars in length)
• The fourth section is a single decimal digit (0 to 9)
• The fifth section must be the '/' char
• The sixth section is an explicit five digit Julian date code
• The seventh section is a 0 to 13 alphanumeric string
• The eighth section must have an alpha char (A to L) followed by two digits
• and the ninth section is a single alphanumeric char

I have the following Regex pattern which seems to match the strings fine but i am unsure how to turn this full pattern into a string and robust way of splitting these strings....

(^\+)(\D\d\d\d)(\w{1,13})(\d)(\/)(\d{5}|\$)(\w{0,13})\D\d\d\w$

I need to turn the above pattern into a form that will allow me to extract each of the matching sections screens.

Thanks in advance

Answer 1

You will need to know about capturing groups. Basically, wrap each "group" that you care about in brackets. Then you can refer to the groups by their ordinal.

For using capturing groups in C#, see this question.

The regex you describe doesn't quite match your inputs though - see the following powershell script.

# Note, I have used **single-quotes**. This is VERY IMPORTANT!
# Powershell interprets a $ as a variable, unless it is inside single-quotes.

# This regex is as described in your comment
$regex = '^(\+)([a-zA-Z]\d{3})(\w{1,13})(\d)(/)(\d{5})(\w{0,13})([A-L]\d{2})(\w)$'
'+H124005992014011/1527399999999I05Z' -match $regex # TRUE
'+H7039700000001/$99999999I051' -match $regex # FALSE
'+K122005962050171/120911234C117' -match $regex # FALSE

# This regex matches all your sample input.
$regex = '^(\+)([a-zA-Z]\d{3})(\w{1,13})(\d)(/)([\d{5}|\$])(\w{0,13})([A-L]\d{2})(\w)$'
'+H124005992014011/1527399999999I05Z' -match $regex 
'+H7039700000001/$99999999I051' -match $regex 
'+K122005962050171/120911234C117' -match $regex

Using Powershell (which uses the same regex engine as C#, so is very suitable for fine-tuning your regex!), you can see the output.