I have a bunch of html files where the filename in the img tag contains whitespaces (). I need to replace whitespaces with underscores (_) in a text editor. I am using this regular expression:
(?<=\/img\/)(\s)(?=.png")
but it doesn't work! Here an example with expected result:
<img src="./img/setup3oval 7 1.png"/>
expected result:
<img src="./img/setup3oval_7__1.png"/>
Any help is very much appreciated
Due to the limitations imposed by the regular expressions, it's not possible to do what you're asking for using a regex in a single run. But you can do it partially:
(?<=src=")(.*?)\s+(.*?)(?=\.)
You've mentioned that you're making use of a text editor to run this regex. If you're using something like Notepad++, you should be able to click the replace button multiple times until you reach the expected result, replacing your text by $1_$2. It shouldn't be too much of a problem if your image file paths doesn't have too much whitespaces in between them.
Explanation of the regex:
(?<=src=") - This is a positive look behind, used to match only strings that are preceeded by this pattern. I'm using the src property as a reference instead of the <img> tag.(.*?)\s+(.*?)- This matches any whitespaces between two blocks of text. I've used lazy quantifiers to avoid wrong matches. I've also wrapped these blocks on capturing groups to use them on substitution.(?=\.) - This is a positive lookahead. The text will match until it reaches a dot character, literally. That is, assuming that there won't be any other dots on the line. You should change this assertion if that's not the case.Demonstration: regex101.com
I've also tested this regex on Notepad++, hitting the substitution button multiple times. The expected results were achieved.
