Only Match String if Text Does Not Contain Another String - regex

I have the following use case. I need a Regex pattern to only match a line, if part of the string does not contain a different string. Here is an example:
<androidx.constraintlayout.widget.Barrier
android:id="#+id/barrier6"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="12dp"/>
So here I want to match android:layout_marginStart="12dp" so that I can replace with:
android:layout_marginStart="12dp"
android:layout_marginLeft="12dp"
I have worked this one out and I can use the following regex to do it:
Find: (.*)android:layout_marginStart="(.*)"
Replace: $1android:layout_marginStart="$2"\n$1android:layout_marginLeft="$2"
What I can't do is conditionally match. I do not want to match if this xml object already contains the android:layout_marginLeft attribute.

In regex, if you want to check to make sure a string is not coming up after the part you wish to match, you can use a negative lookahead.
In this example, you want to match something, but only if the string layout_marginLeft is not coming up later. You can do that, but throwing layout_marginLeft into a negative lookahead, like this:
(?:(?!layout_marginLeft).)*
Now, when you combine that with what you actually want to match your regex would look something like this:
(android:layout_marginStart="(.*?)")(?:(?!layout_marginLeft).)*(?=/>)
And then your replacement string would look like this:
\1\n\t\tandroid:layout_marginLeft="\2"
So, the replacement stuff works the same way, it's just that you are telling it not to do a replacement on anything that already contains layout_marginLeft.
Here is a demo

Related

RegEx substract text from inside

I have an example string:
*DataFromAdHoc(cbgv)
I would like to extract by RegEx:
DataFromAdHoc
So far I have figured something like that:
^[^#][^\(]+
But Unfortunately without positive result. Do you have maybe any idea why it's not working?
The regex you tried ^[^#][^\(]+ would match:
From the beginning of the string, it should not be a # ^[^#]
Then match until you encounter a parenthesis (I think you don't have to escape the parenthesis in a character class) [^\(]+
So this would match *DataFromAdHoc, including the *, because it is not a #.
What you could do, it capture this part [^\(]+ in a group like ([^(]+)
Then your regex would look like:
^[^#]([^(]+)
And the DataFromAdHoc would be in group 1.
Use ^\*(\w+)\(\w+\)$
It just gets everything between the * and the stuff in brackets.
Your answer may depend on which language you're running your regex in, please include that in your question.

Regular Expressions - Select the Second Match

I have a txt file with <i> and </i> between words that I would like to remove using Editpad
For example, I'd like to keep when it's like this:
<i>Phrases and words.</i>
And I'd like to remove the </i> and <i> tags inside the phrase, when it's like this:
<i>Phrases</i>and<i> words.</i>
<i>Phrases</i>and <i>words.</i>
I was trying to do that using regex, but I couldn't do it.
As the tag is followed by space or a word character I could find when the line has the double tag with
/ <i>|<\/i> /
but this way I can't just press replace for nothing, I have to edit line by line I search.
There's anyway to accomplish that?
* Edited *
Another example of lines found on the subtitle text
<i>- find me on the chamber.</i>
- What? <i>Go. Go, go, go!</i>
Rule number one: you can't parse html with regex.
That being said, if you know each line follows a certain pattern, you can usually hack something together to work. ;)
If I've understood correctly, it looks like you can simply remove all <i> and </i> that aren't either at the beginning or end of the lines. In that case, one method you could try is the following regex:
(?<=.)\<\/?i\>(?=.)
This will match the tags, with a lookahead and behind to make sure that we aren't at the end/start of a line (by checking if another character exists in front/behind. (Note that typically matched characters in a lookahead/behind won't be replaced when you search/replace.)
Disclaimer: this works on regex101, but notepad++ may have some differences to the pcre regex style.
update to work with Editpad
EDIT: since this question is actually wanting to know how to do this in Editpad, below is a modified alternative:
Try searching for the regex: (.)\<\/?i\>(.). This will match (and capture) exactly one character before and after the <i> tags.
When replacing, use backreferences to replace the entire match with the two captured characters - a replacement string of \1\2 should work.

Regex: Negative lookahead after list match

Consider the following input string (part of css file):
url('data:image/png;base64,iVBORw0KGgoAAAAN...');
url(example.png);
The objective is to take the url part using regex and do something with it. So the first part is easy:
url\(['"]?(.+?)['"]?\)
Basically, it takes contents from inside url(...) with optional quotes symbols. Using this regexp I get the following matches:
data:image/png;base64,iVBORw0KGgoAAAAN...
example.png
So far so good. Now I want to exclude the urls which include 'data:image' in their text. I think negative lookahead is the proper tool for that but using it like this:
url\(['"]?(?!data:image)(.+?)['"]?\)
gives me the following result for the first url:
'data:image/png;base64,iVBORw0KGgoAAAAN...
Not only it doesn't exclude this match, but the matched string itself now includes quote character at the beginning. If I use + instead of first ? like this:
url\(['"]+(?!data:image)(.+?)['"]?\)
it works as expected, url is not matched. But this doesn't allow the optional quote in url (since + is 1 or more). How should I change the regex to exclude given url?
You can use negative lookahead like this:
url\((['"]?)((?:(?!data:image).)+?)\1?\)
RegEx Demo

How can I write a regular expression match for a string that must contain the following characters: thankYou.sjs?donate_page

I need to create a regex query for a Google Analytics goal. The goal url must contain:
thankYou.sjs?donate_page
However, there are many urls than can render this string, all with other modifiers that I don't care about.
Please advise.
#ExplosionPills: I think you forgot about the special meaning of the question mark.
If you don't escape it, your expression:
^thankYou.sjs?donate_path$
Would match
thankYou.sjsdonate_path
or
thankYou.sjdonate_path
Not to mention the special meaning of dot.
So I guess something like this should work:
thankYou\.sjs\?donate_path
Furthermore if it's possible that the donate_path is not the first in the query string you can use this:
thankYou\.sjs\?([^&]*&)*donate_path
Just the string itself will work. If you want only this string, just use the start/end of string zero-width assertions:
^thankYou\.sjs\?donate_path$

How to match a string that does not end in a certain substring?

how can I write regular expression that dose not contain some string at the end.
in my project,all classes that their names dont end with some string such as "controller" and "map" should inherit from a base class. how can I do this using regular expression ?
but using both
public*.class[a-zA-Z]*(?<!controller|map)$
public*.class*.(?<!controller)$
there isnt any match case!!!
Do a search for all filenames matching this:
(?<!controller|map|anythingelse)$
(Remove the |anythingelse if no other keywords, or append other keywords similarly.)
If you can't use negative lookbehinds (the (?<!..) bit), do a search for filenames that do not match this:
(?:controller|map)$
And if that still doesn't work (might not in some IDEs), remove the ?: part and it probably will - that just makes it a non-capturing group, but the difference here is fairly insignificant.
If you're using something where the full string must match, then you can just prefix either of the above with ^.* to do that.
Update:
In response to this:
but using both
public*.class[a-zA-Z]*(?<!controller|map)$
public*.class*.(?<!controller)$
there isnt any match case!!!
Not quite sure what you're attempting with the public/class stuff there, so try this:
public.*class.*(?<!controller|map)$`
The . is a regex char that means "anything except newline", and the * means zero or more times.
If this isn't what you're after, edit the question with more details.
Depending on your regex implementation, you might be able to use a lookbehind for this task. This would look like
(?<!SomeText)$
This matches any lines NOT having "SomeText" at their end. If you cannot use that, the expression
^(?!.*SomeText$).*$
matches any non-empty lines not ending with "SomeText" as well.
You could write a regex that contains two groups, one consists of one or more characters before controller or map, the other contains controller or map and is optional.
^(.+)(controller|map)?$
With that you may match your string and if there is a group() method in the regex API you use, if group(2) is empty, the string does not contain controller or map.
Check if the name does not match [a-zA-Z]*controller or [a-zA-Z]*map.
finally I did it in this way
public.*class.*[^(controller|map|spec)]$
it worked