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Stop regex from spanning across unrequired content

I need to extract a series of meaningful values from a file. The basic pattern for the values I need to match looks like:
"indicator\..+?"\[true\]
Unfortunately, in places this is spanning across quite a bit of content to get a true match, and the lazy quantifier (?) is not being as lazy as I'd like.
How do I modify the above so that out of the following:
"indicator.value here"[false],"other content","more other
content","indicator don't match this one because the full stop is missing"[true],"indicator.this is the
value I want matched"[true]
only this value is returned: "indicator.this is the value I want matched"[true]
Currently, that whole string is being returned by my above regex.

Assuming commas are the delimiter - simply avoid matching on them:
#"""indicator\.[^,]+?""\[true\]"

Try using "indicator\.(.*)?"\[true\] instead and see if that helps. I think the lazy only applies to the * operator. I vaguely remember having this issue years ago.

You can leverage the discard technique by discarding the pattern you don't want. So, you could have something like this:
"indicator\..+?"\[false\]|"indicator\.(.+?)"\[true\]
Discard this pattern --^ Capture this --^
Working demo
Match information
MATCH 1
1. [150-182] `this is the value I want matched`

Parsing Log using something else than string split c#

I'm pretty sure it has been asked before, but I could not find anything good.
I'm trying to parse a log but having troubles with it.
At first it looked pretty easy because the log is build like this:
thing,thing,thing,thing
so I string split it on the ,
however in the value itself it is possible that a , appears, and this is where I did not know what to do anymore.
How would I successfully parse this kind of log?
Edit~~
here is an log example:
1326139200953,info,,0,"str value which may contain, ",,,0
1326139201109,info,,0,"str value which may contain, ",,,0
1326139201265,info,,0,"str value which may contain, ",,,0
1326139201999,start,,0,,,,0
1326139368296,new,F:\Dir\Dir\file.txt,1536,,0,,0
``

If your log file doesn't have field encapsulators, the fields have variable width, and the separator/delimiter can also appear in a field, then it's likely you can't program something that will work in all cases.
Can you supply an example of your log file data? It may be possible to match the parts you need with a regex.
Unfortunately I think your question is not answerable in its current state, please provide more info.
Edit: Thanks for updating the question, you do have field encapsulators (double quotes). This will make it easier!
I think there are many ways to do this. Personally i think i would carry on splitting on commas, but then loop over the resulting array, checking if the first character of any value is a double quote. If it is, then you need to join it to the array item after it. If the last character of the joined array item isn't a double quote, you need to continue joining until you've closed your opening double quote.
There's certainly a better way so you may wish to wait for another solution.
Edit 2: Give this a go and let me know how you get on:
string myRegex = #"(?<=^(?:[^""]*""[^""]*"")*[^""]*),";
string[] outputArray = Regex.Split(myStr, myRegex);

How to convert words to links?

I have a xml with two properties: word and link.
How can I replace the words on a text to a link using the xml information.
Ex.:
XML
<word>dog</word>
<link>http://www.dog.com</link>
Text: The dog is nice.
Result: The dog is nice.
Results OK.
The problems:
1- If the text has the word dogs the result is incorret, because of "s".
2- I've tested doing a split by space on text to fix it, but if the word is composed like new year the result is incorret again.
Does anyone have any suggestions to do it and fix these problems (plural and compound words)?
Thanks for the help.

You can use Lucene.Net's contrib package Snowball for stemming (words->word , came->come , having->have etc.). But you will still have troubles with compound words

If you roll your own solution, I have had good success with the .NET pluralization capabilities:
http://msdn.microsoft.com/en-us/library/system.data.entity.design.pluralizationservices.pluralizationservice.aspx
Essentially, you can pass a word in its plural form and receive a singular version and vice versa.
This could be fairly intensive depending on how often the content changed, i.e. this wouldn't be a good choice to search thousands of words in real time.
Assuming that you can pre-process/cache the results or that the source file is small, you could:
Run Once
Identify all candidate words from the source file.
Parse/split phrases and pass them through the pluralization libraries to determine their plural counterparts.
Generate (and precompile) simple regular expressions to locate the words that you do want to match. For example, if you want to match "dog" but not "dogs" you could create a regex like dog[^s] which could then be executed against the text.
Run Whenever a Search/Replace is Needed
Run your list of source expressions against the text in question. I would suggest ordering the expressions from shortest to longest (otherwise a short expression may replace a word that was just parsed by a longer expression).
Again, this would be processor intensive to run in real-time (most solutions will be). As always, if you are parsing HTML, you should use an HTML parser, not a regular expression. In this case, you might use a proper parser to locate all text nodes and then perform the search/replace on them.
An alternative solution would be to put the text and keyword list into a database and use SQL Server Full Text Indexing which tends to be pretty smart about these things and supports intelligent match predicates. You could even combine this with a CLR stored procedure to handle things that .NET excels at (like string parsing).
Regardless of the approach, this will not be an exact science.

You're likely going to need a dictionary. Create a text file/XML file that contains both the singular and plural forms of the words you want. At runtime, load them into a Dictionary<String, String>. Then look up the value of <word/> in the dictionary and extract its singular value.

Parsing a CSV File with C#, ignoring thousand separators

Working on a program that takes a CSV file and splits on each ",". The issue I have is there are thousand separators in some of the numbers. In the CSV file, the numbers render correctly. When viewed as a text document, they are shown like below:
Dog,Cat,100,100,Fish
In a CSV file, there are four cells, with the values "Dog", "Cat", "100,000", "Fish". When I split on the "," to an array of strings, it contains 5 elements, when what I want is 4. Anyone know a way to work around this?
Thanks

There are two common mistakes made when reading csv code: using a split() function and using regular expressions. Both approaches are wrong, in that they are prone to corner cases such as yours and slower than they could be.
Instead, use a dedicated parser such as Microsoft.VisualBasic.TextFieldParser, CodeProject's FastCSV or Linq2csv, or my own implemention here on Stack Overflow.

Typically, CSV files would wrap these elements in quotes, causing your line to be displayed as:
Dog,Cat,"100,100",Fish
This would parse correctly (if using a reasonable method, ie: the TextFieldParser class or a 3rd party library), and avoid this issue.
I would consider your file as an error case - and would try to correct the issue on the generation side.
That being said, if that is not possible, you will need to have more information about the data structure in the file to correct this. For example, in this case, you know you should have 4 elements - if you find five, you may need to merge back together the 3rd and 4th, since those two represent the only number within the line.
This is not possible in a general case, however - for example, take the following:
100,100,100
If that is 2 numbers, should it be 100100, 100, or should it be 100, 100100? There is no way to determine this without more information.

you might want to have a look at the free opensource project FileHelpers. If you MUST use your own code, here is a primer on the CSV "standard" format

well you could always split on ("\",\"") and then trim the first and last element.
But I would look into regular expressions that match elements with in "".

Don't just split on the , split on ", ".
Better still, use a CSV library from google or codeplex etc
Reading a CSV file in .NET?

You may be able to use Regex.Replace to get rid of specifically the third comma as per below before parsing?
Replaces up to a specified number of occurrences of a pattern specified in the Regex constructor with a replacement string, starting at a specified character position in the input string. A MatchEvaluator delegate is called at each match to evaluate the replacement.
[C#] public string Replace(string, MatchEvaluator, int, int);

I ran into a similar issue with fields with line feeds in. Im not convinced this is elegant, but... For mine I basically chopped mine into lines, then if the line didnt start with a text delimeter, I appended it to the line above.
You could try something like this : Step through each field, if the field has an end text delimeter, move to the next, if not, grab the next field, appaend it, rince and repeat till you do have an end delimeter (allows for 1,000,000,000 etc) ..
(Im caffeine deprived, and hungry, I did write some code but it was so ugly, I didnt even post it)

Do you know that it will always contain exactly four columns? If so, this quick-and-dirty LINQ code would work:
string[] elements = line.Split(',');
string element1 = elements.ElementAt(0);
string element2 = elements.ElementAt(1);
// Exclude the first two elements and the last element.
var element3parts = elements.Skip(2).Take(elements.Count() - 3);
int element3 = Convert.ToInt32(string.Join("",element3parts));
string element4 = elements.Last();
Not elegant, but it works.

Quick & Dirty way to update "IDs" in a string formatted as XML (C#)

For a one-shot operation, i need to parse the contents of an XML string and change the numbers of the "ID" field. However, i can not risk changing anything else of the string, eg. whitespace, line feeds, etc. MUST remain as they are!
Since i have made the experience that XmlReader tends to mess whitespace up and may even reformat your XML i don't want to use it (but feel free to convince me otherwise). This also screams for RegEx but ... i'm not good at RegEx, particularly not with the .NET implementation.
Here's a short part of the string, the number of the ID field needs to be updated in some cases. There can be many such VAR entries in the string. So i need to convert each ID to Int32, compare & modify it, then put it back into the string.
<VAR NAME="sf_name" ID="1001210">
I am looking for the simplest (in terms of coding time) and safest way to do this.

The regex pattern you are looking for is:
ID="(\d+)"
Match group 1 would contain the number. Use a MatchEvaluator Delegate to replace matches with dynamically calculated replacements.
Regex r = new Regex("ID=\"(\\d+)\"");
string outputXml = r.Replace(inputXml, new MatchEvaluator(ReplaceFunction));
where ReplaceFunction is something like this:
public string ReplaceFunction(Match m)
{
// do stuff with m.Groups(1);
return result.ToString();
}
If you need I can expand the Regex to match more specifically. Currently all ID values (that contain numbers only) are replaced. You can also build that bit of "extra intelligence" into the match evaluator function and make it return the match unchanged if you don't want to change it.

Take a look at this property PreserveWhitespace in XmlDocument class