How can I search a paragraph for one or more sentences using PHP?
Yes. strpos will tell you whether a string exists within a string.
Have a look over here, maybe here and here.
Well, you'll probably want to use "preg_match()" if possible (requires knowledge of regular expressions though). "strstr()" works too if you know exactly what you want to find.
Related
Tried different regex generators with no luck.
I have this string that i put in preg_match:
$search_string = "/^:([A-Za-z0-9_\-]+)[#!~a-zA-Z0-9#\.\-]+\s*([A-Z]+)\s*[:]*([\#a-zA-Z0-9\-]+)*\s*[:]*([!\#\-\.A-Za-z0-9 ]+)*/";
It's basically for usernames. Sadly, when username has underscore in it. For example iam_coolguy wouldn't work.
How to add underscore to this search string?
I can't seem to figure out how regex works.
It's not a duplicate, scrolled past all preg_match threads.
/[a-z]/i seems easy and understandable for me, but my string is too advanced for my knowledge.
Thanks.
If you are just looking to grab somthing between //'s
I would just use this regex \/(.*)\/
but as the others have said, you havent given any limitations on what the username can and can't have in it.
If you need more, say something and I will adjust my answer.
I have created one regex that can extract all string from PHP files.
Example, I have "abc.php", I want to extract all string inside there (including tags " ' ).
I make my own regex but some of string didn't match or overmatch.
Note : My intention also same with post here -> PHP: Regex to match the following string samples
But agent-j answers inside that thread also didn't match some of string.
Basically, this is my regex
/[\"|\'][^.\/\"](.*?)[^,\\][\"|\']/
Here the problem in picture..
I also try use agent-j regex, but his regex has problem when matching string in multiple line.
His regex
(['"])((?:\\\1|(?!\1).)+)\1
Problem with this regex
The easiest way I have ever found to regex match any logic to an entire file has been to use
$something_better = explode(''',$something);
This way you get an array of data that is more easily evaluated. I use this concept every time I want to guarantee I can make the match exactly how I want every time.
What I would do here is to explode and extract the info between single quotes, matching what I wanted from them, and then implode on the single quote. Since you also want the double quotes, you can then explode and repeat the process for double quotes.
In my experience it is very hard to regex all your problems away in one simple statement. It's better to take it in smaller pieces if you can. There will be less room for error.
Look like anybody don't solve my problem.
I solved this problem myself with help of my friend.
So this is the regex that i was looking for.
/([\"\'])(?:(?=(\\\\?))\\2.)*?\\1/s
Is it possible to display the strings that match a regular expression?
Example:
Take the expression /^AD\d{3}/
and display AD999
What I'm doing is validating a string that is pretty simple either containing all numbers, a few characters maybe, and maybe a '-'. I am validating a postal code on form submit against a database of all countries that use a postal code.
I could perform it in Javascript or PHP, if that makes any difference.
No. That sort of feature is not available.
You can try to implement it yourself, but I don't think that's the solution for you. Simply write the messages normally. Not everything must always be dynamic.
I like your way of thinking though.
It is possible. The developers of PEX figured it out.
Don't get your hopes up, I don't know of any javascript implementation.
There is one for javascript now: http://fent.github.io/randexp.js/.
I have understood your problem a little better from your additional comments.
Since your data is only postal codes, I suggest that it would possible to work in the other direction and store a picture in the database and automatically generate a regex from that.
For instance, UK postcodes look like AA?99? 9AA | AA?9A 9AA which is easily converted to a regex (using a regex!).
This question already has answers here:
Closed 12 years ago.
Possible Duplicate:
PHP - How to split a paragraph into sentences.
I have a block of text that I would like to separate into sentences, what would be the best way of doing this? I thought of looking for '.','!','?' characters, but I realized there were some problems with this, such as when people use acronyms, or end a sentence with something like !?. What would be the best way to handle this? I figured there would be some regex that could handle this, but I'm open to a non-regex solution if that fits the problem better.
Regex isn't the best solution for this problem. You'd be served better by creating a parsing library. Something where you an easily create logic blocks to distinguish one thing from another. You'll need to come up with a set of rules breaking up the text into the chunks you'd like to see.
"Are you sure?" he asked.
Doesn't that mess things up when using regex? However, with a parser you could actually see
<start quote><capitalization>are you sure<question><end quote>he asked<period>
that with simple rules could say "that's one sentence."
Unfortunately there is no perfect solution for this, for the very reasons you stated. If it is content that you can somehow control or force a specified delimiter after every sentence, that would be ideal. Beyond that, all you can really do is look for (\.|!|?)+ and maybe even throw in a \s after that since most people pad new sentences with 1 or 2 spaces between the previous and next sentence.
I think the biggest problem is the possible existence of acronyms! Therefore you must use something like Prof. Knuth in a JavaDoc summary sentence so that the javadoc generator don't thinks that the first sentence ends after Prof..
This is a problem I don't know how anyone can reliably handle. The only approximate solution I could imagine is the use of an abbreviation dictionary.
I have looked at many questions here (and many more websites) and some provided hints but none gave me a definitive answer. I know regular expressions but I am far from being a guru. This particular question deals with regex in PHP.
I need to locate words in a text that are not surrounded by a hyperlink of a given class. For example, I might have
This elephant is green and this elephant is blue while this elephant is red.
I would need to match against the second and third elephants but not the first (identified by test class "no_check"). Note that there could more attributes than just href and class within hyperlinks. I came up with
((?<!<a .*class="no_check".*>)\belephant\b)
which works beautifully in regex test software but not in PHP.
Any help is greatly appreciated. If you cannot provide a regular expression but can find some sort of PHP code logic that would circumvent the need for it, I would be equally grateful.
If variable width negative look-behind is not available a quick and dirty solution is to reverse the string in memory and use variable width negative look-ahead instead. then reverse the string again.
But you may be better off using an HTML parser.
I think the simplest approach would be to match either a complete <a> element with a "no_check" attribute, or the word you're searching for. For example:
<a [^<>]*class="no_check"[^<>]*>.*?</a>|(\belephant\b)
If it was the word you matched, it will be in capture group #1; if not, that group should be empty or null.
Of course, by "simplest approach" I really meant the simplest regex approach. Even simpler would be to use an HTML parser.
I ended up using a mixed solution. It turns out that I had to parse a text for specific keywords and check if they were already part of a link and if not add them to a hyperlink. The solutions provided here were very interesting but not exactly tailored enough for what I needed.
The idea of using an HTML parser was a good one though and I am currently using one in another project. So hats off to both Alan Moore and Eric Strom for suggesting that solution.