I'm working of filtering comments. I'd like to replace string like this:
llllolllllllllllooooooooooooouuuuuuuuuuuddddddddddddddllllollllllllllllloooooooooooooooooouuuuuuuuuuuuuuuuuuddddddddddddddllllollllllllllllloooooooooooooooooouuuuuuuuuuuuuuuuuuddddddddddddddllllollllllllllllloooooooooooouuuuuuuuuuuuuuuuudddddddddddddd
with two words: lol loud
string like this:
cuytwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww
with: cuytw
And string like this:
hyyuyuyuyuyuyuyuyuyuyuyuyuyu
with: hyu
but not modify strings like look, geek.
Is there any way to achieve this with single regular expression in C#?
I think I can answer this categorically.
This definitely cant be done with RegEx or even standard code due to your input and output requirements without at minimum some sort of dictionary and algorithm to try and reduce doubles in a permutation check for legitimate words.
The result (at best) would give you a list of possible non mutually-exclusive combinations of nonsense words and legitimate words with doubles.
In fact, I'd go as far to say with your current requirements and no extra specificity on rules, your input and output are generically impossible and could only be taken at face value for the cases you have given.
I'm not sure how to use RegEx for this problem, but here is an alternative which is arguably easier to read.*
Assuming you just want to return a string comprising the distinct letters of the input in order, you can use GroupBy:
private static string filterString(string input)
{
var groups = input.GroupBy(c => c);
var output = new string(groups.Select(g => g.Key).ToArray());
return output;
}
Passes:
Returns loud for llllolllllllllllooooooooooooouuuuuuuuuuuddddddddddddddllllollllllllllllloooooooooooooooooouuuuuuuuuuuuuuuuuuddddddddddddddllllollllllllllllloooooooooooooooooouuuuuuuuuuuuuuuuuuddddddddddddddllllollllllllllllloooooooooooouuuuuuuuuuuuuuuuudddddddddddddd
Returns cuytw for cuytwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww
Returns hyu for hyyuyuyuyuyuyuyuyuyuyuyuyuyu
Failures:
Returns lok for look
Returns gek for geek
* On second read you want to leave words like look and geek alone; this is a partial answer.
Related
I'm translating a Unity game and some of the lines go like
Unlock at XXXX
where "XXXX" is replaced at runtime by an arbitrary substring. Easy enough to replace the wildcards, but to translate the quote, I can't simply concatenate a + b, as some languages will have the value before or inside the string. I figured I needed to, effectively, de-replace it, ie isolate and keep the substring and translate whatever's around it.
Problem is that while I can easily do the second part, I can't think of any avenues for the first. I know to get the character index of what I'm looking for, but the value takes up an arbitrary number of characters, and I can't use whitespace since some languages don't use it. Can't use digit detection since not all of the values are going to be numbers. I tried asking Google, but I couldn't translate "find whatever replaces a wildcard" into something keyword-searchable.
In short, what I'm looking for is a way to find the "XXXX" (the easy part) and then find whatever replaces it in the string (the less-easy part).
Thanks in advance.
I eventually found a workaround, thanks to everybody's kind advice. I stored the substring and referred to it in a special translation method that does take in a value. Thanks for your kind help, everybody.
public static string TranslateWithValue (string text, string value, int language) {
string sauce = text.Replace (value, "XXXX");
sauce = Translate (sauce, language);
sauce = sauce.Replace ("XXXX", value);
return sauce;
}
Usually, I use string.Format in such cases. In your case, I'd declare 2 localizeable strings:
string unlockFormat = "Unlock at {0}";
string unlockValue = "next level";
When you need the unlock condition displayed, you can combine the strings like that:
string unlockCondition = string.Format(unlockFormat, unlockValue);
which will produce the string "Unlock at next level".
Both unlockFormat and unlockValue can be translated, and the translator can move {0} wherever needed.
i'm a bit confused with regex, i have a line which looks like something like this :
test = "article;vendor;qty;desc;price1;price2"
and what i'm trying to do is to only get price1.
I'm currently using this function :
Regex.Replace(test, #".*;[^;]*;", "");
which permit me to get price2 but I can't see how I can isolate price1.
Have you consider just using a String.Split() call instead to break your current semi-colon delimited string into an array :
var input = "article;vendor;qty;desc;price1;price2";
var output = input.Split(';');
And then you could simply access your value by its index :
var result = output[4]; // yields "price1"
You will only want to use a Regular Expression if there is a specific pattern that you can use to match and select exactly what you are looking for, but for delimited lists, the String.Split() method will usually make things easier (especially if there is nothing to uniquely identify the item you are trying to pull from the list).
Use the following regex:
(?:[^;]*;){4}([^;]*);
And replace the first match group.
Before I look into doing this myself, is there already a function out there that will do this:
I want to pass in a string containing text and RegEx markup and then it returns all possible matches it would look for in a string.
so the following passed to the method
abc|def|xyz
Would return 3 strings in an array or collection:
abc
def
xyz
Because that regex notation says to look for either abc, def or xyz.
I don't want this to search for the term in another string or anything like that, just return the possible matches it could make.
That's a simple example, anything that will do this for me, or shall I start writing the method myself?
With a simple regex as per your example it will work, but as soon as you start dealing with wild cards and repetition, it will have to generate almost an infinite amount of possible solutions, which in some cases may never even terminate.
No, it does not :)
So, Im trying to make a program to rename some files. For the most part, I want them to look like this,
[Testing]StupidName - 2[720p].mkv
But, I would like to be able to change the format, if so desired. If I use MatchEvaluators, you would have to recompile every time. Thats why I don't want to use the MatchEvaluator.
The problem I have is that I don't know how, or if its possible, to tell Replace that if a group was found, include this string. The only syntax for this I have ever seen was something like (?<group>:data), but I can't get this to work. Well if anyone has an idea, im all for it.
EDIT:
Current Capture Regexes =
^(\[(?<FanSub>[^\]\)\}]+)\])?[. _]*(?<SeriesTitle>[\w. ]*?)[. _]*\-[. _]*(?<EpisodeNumber>\d+)[. _]*(\-[. _]*(?<EpisodeName>[\w. ]*?)[. _]*)?([\[\(\{](?<MiscInfo>[^\]\)\}]*)[\]\)\}][. _]*)*[\w. ]*(?<Extension>\.[a-zA-Z]+)$
^(?<SeriesTitle>[\w. ]*?)[. _]*[Ss](?<SeasonNumber>\d+)[Ee](?<EpisodeNumber>\d+).*?(?<Extension>\.[a-zA-Z]+)$
^(?<SeriesTitle>[\w. ]*?)[. _]*(?<SeasonNumber>\d)(?<EpisodeNumber>\d{2}).*?(?<Extension>\.[a-zA-Z]+)$
Current Replace Regex = [${FanSub}]${SeriesTitle} - ${EpisodeNumber} [${MiscInfo}]${Extension}
Using Regex.Replace, the file TestFile 101.mkv, I get []TestFile - 1[].mkv. What I want to do is make it so that [] is only included if the group FanSub or MiscInfo was found.
I can solve this with a MatchEvaluator because I actually get to compile a function. But this would not be a easy solution for users of the program. The only other idea I have to solve this is to actually make my own Regex.Replace function that accepts special syntax.
It sounds like you want to be able to specify an arbitrary format dynamically rather than hard-code it into your code.
Perhaps one solution is to break your filename parts into specific groups then pass in a replacement pattern that takes advantage of those group names. This would give you the ability to pass in different replacement patterns which return the desired filename structure using the Regex.Replace method.
Since you didn't explain the categories of your filename I came up with some random groups to demonstrate. Here's a quick example:
string input = "Testing StupidName Number2 720p.mkv";
string pattern = #"^(?<Category>\w+)\s+(?<Name>.+?)\s+Number(?<Number>\d+)\s+(?<Resolution>\d+p)(?<Extension>\.mkv)$";
string[] replacePatterns =
{
"[${Category}]${Name} - ${Number}[${Resolution}]${Extension}",
"${Category} - ${Name} - ${Number} - ${Resolution}${Extension}",
"(${Number}) - [${Resolution}] ${Name} [${Category}]${Extension}"
};
foreach (string replacePattern in replacePatterns)
{
Console.WriteLine(Regex.Replace(input, pattern, replacePattern));
}
As shown in the sample, named groups in the pattern, specified as (?<Name>pattern), are referred to in the replacement pattern by ${Name}.
With this approach you would need to know the group names beforehand and pass these in to rearrange the pattern as needed.
Imagine that users are inserting strings in several computers.
On one computer, the pattern in the configuration will extract some characters of that string, lets say position 4 to 5.
On another computer, the extract pattern will return other characters, for instance, last 3 positions of the string.
These configurations (the Regex patterns) are different for each computer, and should be available for change by the administrator, without having to change the source code.
Some examples:
Original_String Return_Value
User1 - abcd78defg123 78
User2 - abcd78defg123 78g1
User3 - mm127788abcd 12
User4 - 123456pp12asd ppsd
Can it be done with Regex?
Thanks.
Why do you want to use regex for this? What is wrong with:
string foo = s.Substring(4,2);
string bar = s.Substring(s.Length-3,3);
(you can wrap those up to do a bit of bounds-checking on the length easily enough)
If you really want, you could wrap it up in a Func<string,string> to put somewhere - not sure I'd bother, though:
Func<string, string> get4and5 = s => s.Substring(4, 2);
Func<string,string> getLast3 = s => s.Substring(s.Length - 3, 3);
string value = "abcd78defg123";
string foo = getLast3(value);
string bar = get4and5(value);
If you really want to use regex:
^...(..)
And:
.*(...)$
To have a regex capture values for further use you typically use (), depending on the regex compiler it might be () or for microsoft MSVC I think it's []
Example
User4 - 123456pp12asd ppsd
is most interesting in that you have here 2 seperate capture areas. Is there some default rule on how to join them together, or would you then want to be able to specify how to make the result?
Perhaps something like
r/......(..)...(..)/\1\2/ for ppsd
r/......(..)...(..)/\2-\1/ for sd-pp
do you want to run a regex to get the captures and handle them yourself, or do you want to run more advanced manipulation commands?
I'm not sure what you are hoping to get by using RegEx. RegEx is used for pattern matching. If you want to extract based on position, just use substring.
It seems to me that Regex really isn't the solution here. To return a section of a string beginning at position pos (starting at 0) and of length length, you simply call the Substring function as such:
string section = str.Substring(pos, length)
Grouping. You could match on /^.{3}(.{2})/ and then look at group $1 for example.
The question is why? Normal string handling i.e. actual substring methods are going to be faster and clearer in intent.