I am trying to write a regular expression for ASP.NET MapPageRoute that matches a specific type of path.
I do not want to match anything with a file extension so I used this regex ^[^.]*$ which worked fine except it also picked up if the default document was requested. I do not want it to pick up the default document so I have been trying to change it to require at least one character. I tried adding .{1,} or .+ to the beginning of the working regex but it stopped working alltogether.
routes.MapPageRoute("content", "{*contentpath}", "~/Content.aspx", true, new RouteValueDictionary { }, new RouteValueDictionary { { "contentpath", #"^[^.]*$" } });
How can I change my regex to accomplish this?
Unfortunately my brain does not seem capable of learning regular expressions properly.
You want to change your * quantifier to +. * matches zero or more times, whereas + matches one or more. So, what you are asking for is this:
^[^.]+$
The regex is accomplishing this: "At the beginning of the string, match all characters that are not ., at least one time, up to the end of the string."
^[^.]+$
zero is to * as one is to +
Related
I'm trying to add some validation in ASP.NET using Regex. Essentially I need to ensure a text box includes both ***ThisString*** and ***ThatString*** including the asterisks.
I can get it to work with one, or one or the other, just not both being present at the same time and at any part of the string.l it's validating.
Thanks
As nanhydrin correctly pointed out, my solution will not work if there are multiple of one of the strings but not the other. If that case may occur, you can check for each string separately for readability's sake
First regular expression- (?:\*{3}ThisString\*{3})
Second regular expression- (?:\*{3}ThatString\*{3})
If matches are found in both cases, you're good to go!
Original Answer:-
This is the regular expression you want: (?:\*{3}(?:ThisString|ThatString)\*{3})
Note: Make sure to have global match on and be sure to escape the asterisks correctly.
If the above expression finds 2 (or more) matches, it means you're good to go.
Explanation:-
The entire thing is in a non capturing group, this is to ensure, everything within does get matched fully
There are 3 stars on each side of the strings, having 3 stars on one side but not the other will not result in a match
Both ThisString and ThatString are in a grouped alternative, this is to reduce clutter, you could totally jam every possible positional pattern but this is just better as position doesn't matter here. ***ThatString*** can come before ***ThisString*** or vice versa.
MAKE SURE to check the length of the matches found, the length must be 2 for your
described condition to be satisfied.
Here's the live demo
Using #Chase's answer I was able to come up with the following:
protected override ValidationResult IsValid(object value, ValidationContext validationContext)
{
Regex thisString = new Regex("(?:\*{3}ThisString\*{3})");
Regex thatString = new Regex("(?:\*{3}ThatString\*{3})");
if (!thisString.IsMatch(value.ToString()) || !thatString.IsMatch(value.ToString()))
{
return new ValidationResult("***ThisString*** and ***ThatString*** are used to generate the email text. Please ensure the text above has both ***ThisString*** and ***ThatString*** somewhere within the text."); }
return ValidationResult.Success;
}
Now if either regex patterns don't match anywhere, it'll return an error.
I'm new to RegEx and am sure this is an easy one. I looked at similar questions, but being new to RegEx, how it all fits together it still fuzzy.
I want my RegEx to:
ignore a single parameter in my URL and match anything that pops up in the first two parameters (/purple/cat/)
match the specific word (/prices)in the last part of the URL
BUT not match the date in the middle/ignore that part (and any other date)
URL string:
/purple/cat/2017/prices
RegEx:
\/.*\/.*(?<!(20[0-17])\/prices$
How about this - it matches anything with /purple/cat/ + any 4-digit number + /prices:
\/purple\/cat\/[0-9][0-9][0-9][0-9]\/prices
P.S. https://regexr.com/ is useful for playing with regex's.
I need to extract the first element ("adidas-originals") after "designer" in the following URL using regular expressions.
xxx/en-ca/men/designers/adidas-originals/shorts
This needs to be done in Google Big Query API (standard SQL). To this end, I have tried several ways to get the desired valued without any success. Below is the best solution that I have found so far which obviously is not the right one as it returns "/adidas-originals/shorts".
REGEXP_EXTRACT(hits.page.pagePath, r'designers([^\n]*)')
Thanks!
The [^\n]* matches 0 or more chars other than a newline, LF, so no wonder it matches too much.
You need a pattern to match up to the next /, so you may use
designers/([^/]+)
Or a more precise:
(?:^|/)designers/([^/]+)
See the regex demo
Details
(?:^|/) - either start of a string or / (you may just use / if designers is always preceded with /)
designers/ a designers/ substring
([^/]+) - Capturing group 1 (just what will be returned with the REGEXP_EXTRACT function): one or more chars other than /.
I am using the Symfony\Component\DomCrawler\Crawler package to find a form with a name containing a number of css special chars
<input name="myfield[0].thing">
I am using
$messageElement = $crawler->filter('input[name=myField[0].thing]');
return $messageElement->attr($attribute);
But I get the error
Symfony\Component\CssSelector\Exception\SyntaxErrorException: Expected "]", but found.
Obviously this is because the symfony css selector is using [ ] to contain the attributes. So If I try an escape all the special chars
$crawler->filter('input[name=myField\[0\]\.thing]');
I now get empty output. How can I fix this?
Bonus question: is it possible to use a wildcard instead? * doesn't seem to work for me.
If you encapsulate the field name it should work, try this:
$messageElement = $crawler->filter('input[name="myField[0].thing"]');
return $messageElement->attr($attribute);.
For the bonus question, you can use a regex match similar to suggested here: wildcard * in CSS for classes
// For matching strings starting with a certain thing notice the ^=
$messageElement = $crawler->filter('input[name^="myField[0]"]');
// For matching strings containing with a certain thing notice the *=
$messageElement = $crawler->filter('input[name*="myField[0]"]');
I've been trying to follow this SO answer to try and write some regex to do a pattern replace with Grunt. My regex understanding is very basic so I'm pretty lost.
Matching
.selector {
background: url('../img/some.filename.png') no-repeat;
}
Output
.selector {
background: url(<%= asset_path 'some.filename.png' %>) no-repeat;
}
I understand something like /url\(.*?g'\)/ig will match the url() tag but I'm not sure how to isolate the filename from within that. Using the Grunt string-replace task to run the replace.
Any pointers?
I have conjured a beast of a regex that I believe does the job. It requires a positive lookbehind and a positive lookahead which I don't know if Grunt supports since I don't know what that is. I'm going to assume it does, otherwise I don't think it's possible without the lookaround.
I tested this regex using C#, so here it is!
Regex:
(?<=url\s*\('([\w\._-]+/)*)([\w\._-]+)(?='\))
Test String:
url ('fruit-veggie/apple_orange-pie/this.is-my_file.png')
I will break this down as it befuzzles even me. This is composed of 3 major parts.
Positive lookbehind:
(?<=url\s*\('([\w\._-]+/)*)
The (?<=) indicates whatever comes between the = and ) has to be part of the pattern that follows, but it will not be part of the match.
url\s*\(' will match url (' with or without spaces.
([\w\._-]+/)* will match any string that contains at least one word character, dot, underscore, or dash, followed by a forward slash. This will consume one folder path. The * at the end will make it consume any number of folders because you might not have a folder to begin with.
Actual file name:
([\w\._-]+)
This is identical to the folder pattern except without the forward slash at the end. This will match files without extensions.
Positive lookahead:
(?='\))
(?=) is the same as the positive lookbehind, except this is a lookahead which will check what comes after the pattern that precedes it.
'\) simply checks that the entire string is followed by a quote and a closing bracket.
For the folder/file name pattern, you will have to tweak it based on what characters would be valid in them. So if for whatever crazy reason they can contain a #, you will have to modify those portions of the regex to include that character.
Hopefully Grunt supports this regex, otherwise I will have wasted my time. But this was a fun challenge regardless!
Update
It seems JavaScript doesn't support lookbehinds. If what you're doing is specific to your current project only, why don't you try using two regex instead of one?
function GetFile (s) {
s = s.replace (/url\s*\('([\w\._-]+\/)*/g, '');
return s.match (/[\w\._-]+(?='\))/)[0];
}
var s = "url ('fruit-veggie/apple_orange-pie/this.is-my_file.png')";
console.log (GetFile (s));
This will erase everything up to but not including the first character of the file name. Then it returns the file name without the end quote and bracket, because JavaScript supports lookaheads.
You can use something like this :
(?:url\((.*?)\))
Demo
Explanation :
In javascript you can give :
var s="url('../img/some.filename.png')";
var ss= /(?:url\((.*?)\))/ ;
console.log(s.match(ss)[0]);