Regular Expression not Working

Question

3.67/5 (3 votes)

See more:

XML

<br/>Partly Cloudy/Win-
d</div>

Using the above two-line string from a web page, why wont this regex string work,
\<\w*\>\w*\s\w*\/\w*\-\r\n\w*\<\/\w*\>, in finding the above string?

The carriage return is not working (\r\n)

It works fine in Expresso but not in VB 2010 pro.

Thnx a bunch in advance for the correct answer.
rspercy60

Posted 22-Mar-11 11:50am

rspercy65

Add a Solution

2 solutions

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Sergey Alexandrovich Kryukov · Answer 1 · 2011-03-22T12:08:00

Solution 1

It won't work this way. To match end-of-line, use '$'. It also depends on option: it ether means end of string or end of any line, see your regex options. The '$' match is much better than character-based match, because it is system-independent: there are few different ways to delimiter lines.

—SA

Posted 22-Mar-11 12:08pm

Sergey Alexandrovich Kryukov

Comments

rspercy65 22-Mar-11 18:38pm

The dollar sign is not working in expresso or Rad Software Regex Designer or VB 10. I used it with
RegexOptions.Multiline. The'$' doesnt seem to work in any of these programs.

Sergey Alexandrovich Kryukov 22-Mar-11 18:44pm

If must be some mistake. Not all features work in all cases, but '$' is a very old and basic one.
I used it everywhere (many different languages and libraries), $ always worked.

I'm sure the problem is different. Did you pay attention to options? The option can be named "multiline" or something...

--SA

rspercy65 22-Mar-11 20:08pm

Using my line above....How would I use it, with the single quotes, braces, brackets...what?

Sergey Alexandrovich Kryukov 22-Mar-11 20:11pm

Sorry, I only paid attention of end-of-line so far...
Could you kindly describe informally what should you match with examples?
--SA

Sergey Alexandrovich Kryukov 22-Mar-11 20:13pm

Also, when you say it doesn't work in VS, what library do you mean? Or IDE?
If you need to process two-line sample, what other samples if would match, and what not?
--SA

rspercy65 22-Mar-11 20:15pm

match the two-lines below(with tags) exactly the same.

<br/>Partly Cloudy/Win-
d</div>

Sergey Alexandrovich Kryukov 22-Mar-11 20:22pm

It it is "exactly the same" search exact substring. Purpose of regex is different.
Your regex attempt also covers a big set of matches: w* means several words, without any detail on what letters are, etc.
--SA

Sergey Alexandrovich Kryukov 22-Mar-11 20:19pm

I would suggest use something like this:

\<br\/\>w*\/w*/<

So far, I don't know your goal exactly though, just to give an idea...

--SA

rspercy65 22-Mar-11 20:27pm

What I need to see is this...
<br/>Partly Cloudy/Win-d</div>

Then I use the Replace statement and remove the(<br/> and </div>) tags and then place the results in a Label in a weather application

Sergey Alexandrovich Kryukov 22-Mar-11 20:41pm

I'm telling you, it should be some variable string. What?!
--SA

rspercy65 22-Mar-11 21:55pm

<br/>Partly Cloudy/Win-
d</div>

We use this string above as the data were going to find.
Using the above two-line string from a web page, we use this regex string,
\<\w*\>\w*\s\w*\/\w*\-\r\n\w*\<\/\w*\>. It works in expresso and Regex Designer and
this is the result '<br/>Partly Cloudy/Win-d</div>'. But, this does not work in Visual Basic 2010 pro. What I am trying to do is get this result so I can use it in a weather five day forecast.

Sergey Alexandrovich Kryukov 22-Mar-11 22:52pm

No, if it is forecast, which seems obvious, it's not "Win-d" every day. You should select definitive criteria for full set of forecasts. Reference the Web site, most likely I'll find out.
--SA

rspercy65 23-Mar-11 4:50am

There is 13 different types, Cloudy, Cloudy/Wind, Partly Cloudy, Rain/Wind/Sleet,
Partly Cloudy/Win-
d...and the list goes on

The html tags are all the same(<br/> and </div>). There is 5 different forecast that I want to retreive. Here is my code
Dim patternAA As String = "<[\w]*/>{1}[\w\s/]*-{1}\r\n[\w\s/]*|\<\w*\/\>\w*\<\/\w*\>" &
"|\<\w*\/\>\w*\s\w*\<\/\w*\>|\<\w*\/\>\w*\s\w*\-\w*\<\/\w*\>|\<\w*\/\>\w*\s\w*\<\w*\/\>" &
"|\<\w*\/\>\w*\s\w*\<\/\w*\>|\<\w*\/\>\w*\s\w*\/\w*\s\w*\<\/\w*\>|\<\w*\/\>\w*\s\w*\s\w*\s\w*\<\/\w*\>" &
"|\<\w*\/\>\w*\s\w*\s\w*\<\/\w*\|\<\w*\/\>\w*\s\w*\/\w*\<\/\w*\>|\<\w*\/\>\w*\/\w*\/\w*\<\/\w*\>"
'Get the five conditions and the Images that we need.
For Each m In Regex.Matches(myTB.Text, patternAA, RegexOptions.Multiline)
strMatch += m.Value
Next
strMatch = strMatch.Replace("<br/>", "")
strMatch = strMatch.Replace("</div>", ",")
' MessageBox.Show(strMatch)
parts3 = Split(strMatch, ",")

lblCon1.Text = parts3(0)
RetrieveForecastA()
lblCon2.Text = parts3(1)
RetrieveForecastB()
lblCon3.Text = parts3(2)
RetrieveForecastC()
lblCon4.Text = parts3(3)
RetrieveForecastD()
lblCon5.Text = parts3(4)
RetrieveForecastE()

This works as long as there is no "carriage return" in the string i need from web page.

Albin Abel 22-Mar-11 22:35pm

You are right "It it is "exactly the same" search exact substring. Purpose of regex is different". OPs pattern is a more generalized one and may result in many matches. My 5

Sergey Alexandrovich Kryukov 22-Mar-11 22:37pm

Isn't this obvious. I still think this is OP's communication problem, and it is not "exactly the same".
Thank you, Albin.
--SA

Albin Abel · Answer 2 · 2011-03-22T16:31:00

Solution 2

Hi
Try this way..

C#

string test=@"bla bla <br/>Partly Cloudy/Win-
            d</div> bla bla";

C#

string pattern2 = "<[\\w]*/>{1}[\\w\\s/]*-{1}\\r\\n[\\w\\s/]*</[\\w]*>";
 Regex reg2 = new Regex(pattern2);
 Match match2 = reg.Match(test, 0);
 MessageBox.Show(reg2.IsMatch(test).ToString());
 MessageBox.Show(match2.ToString());

This is as per your example. But inside the html tags better use [a-zA-Z] because inside html tags only text is allowed.

I suggest take out the carriage return part. Why because it is not guarantee the carriage return occurs at the same place every time.

Posted 22-Mar-11 16:31pm

Albin Abel

Updated 22-Mar-11 16:38pm

v3

Comments

Sergey Alexandrovich Kryukov 22-Mar-11 22:40pm

Seems reasonable, a 5 (taking into account OP did not specify what's needed).
I think '-' and carriage return are redundant: why and HTML itself is wrong: 1) there is not "win- d" (carriage return is the same as blank space), 2) today windy, tomorrow rainy -- it is not a criteria. None of that is your fault.
--SA

Albin Abel 22-Mar-11 23:34pm

It is summer here now. Thanks SAKryukov

Sergey Alexandrovich Kryukov 23-Mar-11 14:01pm

Not _here_. I had to wipe snow on the day you post your good Answer.
--SA