I am trying to use a regex in VB.NET - the language probably shouldn't matter though - I am trying to extract something reasonable out of a very large file name, "\\path\path\path.path.path\path\some_more_stuff_from a name.item_123_456.html"
I would like to extract, from that whole mess, the "item_123_456"
It seems to make sense that I can get everything before a pattern like ".html" , and from it, everything after the last dot ?
I have tried to get at least the last part (the entire string before .html) and I still get no matches:
Dim matches As MatchCollection
Dim regexStuff As New Regex(".*\\.html")
matches = regexStuff.Matches(strINeed)
Dim successfulMatch As Match
For Each successfulMatch In matches
strFound = successfulMatch.Value
Next
The match I experimented with, hoping I might even get everything between a dot and an .html: Regex("\\..*\\.html") returned Nothing as well.
I just can't get regular expressions to work...
.*\.(.*?)\.html
This finds as many characters as possible .* until it comes to ( a dot followed by as few characters as possible followed by a dot html ) (\.(.*?)\.html)
It places the stuff between the dot html and the dot preceding the dot html into a capturing group, which should be in $1. If you need the vb.net code for that I can likely get that as well, but your code looked okay
Your vb code should look something like this:
Dim matches As MatchCollection
Dim regexStuff As New Regex(".*\.(.*?)\.html")
matches = regexStuff.Matches(strINeed)
strFound = matches.Item(0).Groups(1).Value.ToString
It could probably be generalized into this
[^.\\]+\.html
Edit: or, initial dot required
\.[^.\\]+\.html
Related
For example we have a string:
asd/asd/asd/asd/1#s_
I need to match this part: /asd/1#s_ or asd/1#s_
How is it possible to do with plain regex?
I've tried negative lookahead like this
But it didn't work
\/(?:.(?!\/))?(asd)(\/(([\W\d\w]){1,})|)$
it matches this '/asd/asd/asd/asd/asd/asd/1#s_'
from this 'prefix/asd/asd/asd/asd/asd/asd/1#s_'
and I need to match '/asd/1#s_' without all preceding /asd/'s
Match should work with plain regex
Without any helper functions of any programming language
https://regexr.com/
I use this site to check if regex matches or not
here's the possible strings:
prefix/asd/asd/asd/1#s
prefix/asd/asd/asd/1s#
prefix/asd/asd/asd/s1#
prefix/asd/asd/asd/s#1
prefix/asd/asd/asd/#1s
prefix/asd/asd/asd/#s1
and asd part could be replaced with any word like
prefix/a1sd/a1sd/a1sd/1#s
prefix/a1sd/a1sd/a1sd/1s#
...
So I need to match last repeating part with everything to the right
And everything to the right could be character, not character, digit, in any order
A more complicated string example:
prefix/a1sd/a1sd/a1sd/1s#/ds/dsse/a1sd/22$$#!/123/321/asd
this should match that part:
/a1sd/22$$#!/123/321/asd
Try this one. This works in python.
import re
reg = re.compile(r"\/[a-z]{1,}\/\d+[#a-z_]{1,}")
s = "asd/asd/asd/asd/1#s_"
print(reg.findall(s))
# ['/asd/1#s_']
Update:
Since the question lacks clarity, this only works with the given order and hence, I suppose any other combination simply fails.
Edits:
New Regex
reg = r"\/\w+(\/\w*\d+\W*)*(\/\d+\w*\W*)*(\/\d+\W*\w*)*(\/\w*\W*\d+)*(\/\W*\d+\w*)*(\/\W*\w*\d+)*$"
I'm VERY new to using regular expressions, and I'm trying to figure something simple out.
I have a simple string, and i'm trying to pull out the 590111 and place it into another string.
HMax_590111-1_v8980.bin
So the new string would simply be...
590111
The part number will ALWAYS have 6 digits, and ALWAYS have a version and such. The part number might change location inside of the string.. so it needs to be able to work if it's like this..
590111-1_v8980_HMXAX.bin
What regex expression will do this? Currently, i'm using ^[0-9]* to find it if it's in the front of the file.
Try the following Regex:
Dim text As String = "590111-1_v8980_HMXAX.bin"
Dim pattern As String = "\d{6}"
'Instantiate the regular expression object.
Dim r As Regex = new Regex(pattern, RegexOptions.IgnoreCase)
'Match the regular expression pattern against a text string.
Dim m As Match = r.Match(text)
In Regex \d denotes numerics, so first you write \d.
Then as you know there will be a fix length of numbers which can be specified in Regex with "{}". If you specify \d{6} it means it will expect 6 continuous occurrences of a numeric character.
I would recommend to use this site to try your own expressions. Here you can also find a little bit of information about the expressions you are building if you hover over it.
Regex Tester
I have a very large text file that has multiple instances of "CLM*[NUMBER I WANT]*". I have been able to use regex to mostly obtain this thanks to another user on this site, but the results I'm getting are displaying the CLM* portion, when I really just want the number. You can see the relevant code below.
Dim strClaimData As String = ""
Dim strClaimNumber As String = ClaimLoadedGetCLM(strClaimData)
Public Function ClaimLoadedGetCLM(ByVal ediString As String) As String
Dim regex As New Regex("CLM\*(\d*?\*??\d*)")
Dim ClaimMatches As MatchCollection = regex.Matches(strClaimData)
For Each strClaimData As Match In ClaimMatches
lstClaimLoaded837Data.Items.Add(strClaimData.Value)
Next
End Function
I've tried a few things I've found online, such as appending a \K or \2, but I just get compile errors if I do that.
https://regex101.com/r/jH9eJ7/1
That shows what I want as "Match 1, Group 1", but I can't figure out how to get to it. I thought appending /1 would work, but that only returned CLM* with no number.
Any help would be greatly appreciated.
What you want to do is wrap the CLM\* part in a possitive lookbehind assertion:
(?<=CLM\*)
What this does asserts that (\d*\.?\d*) is preceded by CLM*, but doesn't include CLM* in the match.
https://regex101.com/r/jH9eJ7/3
You can tell it to use the captured group.
Replace:
strClaimData.Value
with:
strClaimData.Groups[1].Value
in your for loop.
I have to extract all there is between this caracters:
<a href="/url?q=(text to extract whatever it is)&
I tried this pattern, but it's not working for me:
/(?<=url\?q=).*?(?=&)/
I'm programming in Vb.net, this is the code, but I think that the problem is that the pattern is wrong:
Dim matches As MatchCollection
matches = regex.Matches(TextBox1.Text)
For Each Match As Match In matches
listbox1.items.add(Match.Value)
Next
Could you help me please?
Your regex is seemed to be correct except the slash(/) in the beginning and ending of expression, remove it:
Dim regex = New Regex("(?<=url\?q=).*?(?=&)")
and it should work.
Some utilities and most languages use / (forward slash) to start and end (de-limit or contain) the search expression others may use single quotes. With System.Text.RegularExpressions.Regex you don't need it.
This regex code below will extract all urls from your text (or any other):
(http|ftp|https):\/\/[\w\-_]+(\.[\w\-_]+)+([\w\-\.,#?^=%&:/~\+#]*[\w\-\#?^=%&/~\+#])?
I have strings that look like this
{/CSDC} CHOC SHELL DIP COLOR {17}
I need to extract the value in the first swirly brackets. In the above example it would be
/CSDC
So far i have this code which is not working
Dim matchCode = Regex.Matches(txtItems.Text, "/\{(.+?)\}/")
Dim itemCode As String
If matchCode.Count > 0 Then
itemCode = matchCode(0).Value
End If
I think the main issue here is that you are confusing your regular expression syntax between different languages.
In languages like Javascript, Perl, Ruby and others, you create a regular expression object by using the /regex/ notation.
In .NET, when you instantiate a Regex object, you pass it a string of the regular expression, which is delimited by quotes, not slashes. So it is of the form "regex".
So try removing the leading and trailing / from your string and see how you go.
This may not be the whole problem, but it is at least part of it.
Are you getting the whole string instead of just the 1st value? Regular expressions are greedy by default so .Net is trying to grab the largest matching string.
Try this:
Dim matchCode = Regex.Matches(txtItems.Text, "\{[^}]*\}")
Dim itemCode As String
If matchCode.Count > 0 Then
itemCode = matchCode(0).Groups(0).Value
End If
Edited: I've tried this in Linqpad and it worked.
It appears you are using a capture group.. so try matchCode(0).Groups(0).Value
Also, remove the /\ from the beginning of the pattern and remove the trailing /