Regular Expressions Help... Also help dealing with text

krisnrg

Hey guys a new to PHP and programing in general.

I made a script that will take a song string and transpose the music chords to a different key. Everything is working fine except that some text copied of certain websites like ultimate-guitar tabs will have a new life(\n) right after the Chord...

like this:
Am\n

in my regex i have it to allow and optional space after the chord but for some reason it only works on some strings pasted into my form.

regex:

/\b[A-G](#|b)*(m|M|maj|7|maj7|sus|sus2|sus4|9|4|2)* */

Also I would like to add the word boundry at the end but \b doesn't match a # sign or number so it doesn't work

$ doesn't seem to match at the end of the string so thats why I have it set to match a blank space because most chords have a blank space after them and the ones that don't I add it when I add the space before the \n

Also in the transpose script I have it setup to add a blank space before every \n and it's only working sometimes.. what gives? It seems that some things pasted in have different formating other than \n

Thanks in advanced for the help guys

nrg_alpha

You should include some sample 'song strings' that you may be dealing with, as examples of what would be acceptable as well as some that won't and why. Giving some examples gives us a visual to work off of.

Also I would like to add the word boundry at the end but \b doesn't match a # sign or number so it doesn't work

What you must understand is that \b doesn't match a character, but rather a position / location in a string where there is a word character on one side, and not on the other (look ahead or look behind assertions also do not match characters, but rather locations).

Once I see some samples, I'll be able to comment on your pattern (which I already can see some issued, but will wait till afterwards).

krisnrg

I understand it matches a position but say I want to match

A# exactly

/\b/

cause I don't want a word to the left of it

/\bA#/

right this should match but some text has an \n right after the chords or even an \r(which I recently found out some copied text strings have and that was one of my problems)

now I found that \s will match any space character including space \n \r and tab

/\bA#\s/

but it's not working in my code....

my search looks kinda like this...(im at work right now)
/\bA-G(m|M|maj|7|maj7|sus|sus2|sus4|9|4|2)((\/)(A-G))*\s/

Now I was matching an empty space because sometimes it would pick up

And or God

and the \b won't work with # cause it's not a word character

but I have a string the has
A\r

and I can't find a way to match that.

I'm at work now but at lunch I'll post the exact regex search im doing...