Regex Between Strings and position - regex

Question

I have a confusing string which normally has some form of address in it, in some cases where it is a corner address it is easy as the address has a CNR at the start so i can use the following regex (i am working in vb.net):
Case 1 Instr CNR: Regex = New Regex("( CNR )(.*?)(?=\SVSE| M | SVC | SVSW | SVNE |SVNW )", RegexOptions.RightToLeft)
At the end of the string is normally a map reference, which is what the end is looking for which then allows me to extract the address. Once i have this address i plan to geocode the address to determine the latitude and longitude.
However in some cases there is no address, and the string may contain phrases which suggest to me that the address is after that point for example FIRE NOW OUT JOHN ST SUBURB M 215 G2. If this is the case i use the below regex:
Case 2 No CNR: Regex = New Regex("( ([\d]+) | ([\d]+-[\d]+) | ([\d]+ - [\d]+) | CAR SMOULDERING | INPUT | OFF | OPPOSITE | CNR | SPARKING | INCIC1 | INCIC3 | STRUC1 | STRUC3 | G&SC1 | G&SC3 | ALARC1 | ALARC3 | NOSTC1| NOSTC3 | RESCC1 | RESCC3 | HIARC1 | HIARC3 | CAR ACCIDENT - POSS PERSON TRAPPED | EXPLOSIONS HEARD | WASHAWAY AS A RESULT OF ACCIDENT | ENTRANCE | ENT | LHS | RHS | POWER LINES ARCING AND SPARKING | SMOKE ISSUING FROM FAN | CAR FIRE | FIRE ALARM OPERATING | GAS LEAK | GAS PIPE | NOW OUT | ACCIDENT | SMOKING | ROOF | GAS | REQUIRED | FIRE | LOCKED IN CAR | SMOKE RISING | SINGLE CAR ACCIDENT | ACCIDENT | FIRE)(.*?)(?=\SVSE| M | SVC | SVSW | SVNE | SVNW )", RegexOptions.RightToLeft)
In all cases I work from Right to left, looking to see when the front part of the string is found, then I want to take from the start until just before the map reference. However my question is how can I use the above (Case 2) regex and look for a phrase but not include it, when I may want to include others. For example if the string has a street number then I want to include the number in the extracted string, but if it has REQUIRED then i don't want to extract that. I will give two examples
A: SPECIAL APPLIANCE TYPE-A REQUIRED EXAMPLE ST SUBURB M 215 G5
B: HOUSE FIRE 123 EXAMPLE ST SUBURB M 215 G5
In case A, REQUIRED is not part of the address, so I don't want the regex to include that in the extracted address, and it would output as a string EXAMPLE ST SUBURB.
In case B, since a street address exists I don't want to exclude that, so the extracted address would be 123 EXAMPLE ST SUBURB.
So the question is in the above regex, how can I extract the string between phrases, and include the phrase in some cases, and exclude it in others?
Sorry for such a big question, I wanted to make sure I provided enough information.
The final question is, does regex allow you to work out where the first part matches (e.g. the length in the string) so for example in the above REQUIRED part, it is 35 characters after REQUIRED appears, and the Regex extracts the string EXAMPLE ST SUBURB. Can i have the regex return the position of the first match, so I can extract additional information from the string (e.g. from Start of string, until Regex Position A extracts: SPECIAL APPLIANCE TYPE-A REQUIRED).
Thanks for your help!

Answer 1

I got one of the parts of the question, using the match.index and match.length allowed me to work out where the string actually ended (e.g. the position) from there i can do the bits and pieces I wanted to.
The only bit i could not work out is how i can use a regex example like below and include CNR in the string returned (e.g. the regex match) if it is found but not include STREET1 or ROAD1:
Regex = New Regex("( CNR ||)(.*?)(?=\SVSE| M | SVC | SVSW | SVNE |SVNW )", RegexOptions.RightToLeft)
For example if my string is: EXAMPLE TEXT CNR 123 STREET A SUBURB M 215 G2 it would return CNR 123 STREET A SUBURB but if my string was EXAMPLE TEXT STREET1 STREET A SUBURB M 215 G2 then it would return STREET A SUBURB\
I should point out though, that STREET1 in the above example is the point at which the regex starts / finishes, but is just not included in the match, since STREET A may be a different phrase i can't just look for STREET A
Thanks!