I need to remove lines that have the following characteristics.
<img src="index-1_2.jpg"/><br>
<img src="index-1_3.jpg"/><br>
<img src="index-1_5.jpg"/><br>
<img src="index-2_1.jpg"/><br>
<img src="index-2_5.jpg"/><br>
<img src="index-3_1.png"/><br>
<img src="index-23_8.png"/><br>
<img src="index-22_9.png"/><br>
<img src="index-22_1.jpg"/><br>
<img src="index-22_2.jpg"/><br>
<img src="index-99_5.png"/><br>
<img src="index-100_5.png"/><br>
<img src="index-1000_5.png"/><br>
...
As you can see, the number that is found after the word index and after the _ and also, the image format (png, jpg) varies.
I need to generate a regex that removes all these lines EXECPTING numbers found after the index. For example, I need to keep the lines that have only the numbers 1 and 2.
I have the following generated regular expression
^<img src="index-(?!2|1)\d+_\d+\.(?:jpg|png)"\/><br>$
but wanting to keep the numbers 1 and 2, it also keeps the numbers 22, 23, 100 and 1000 since they contain those numbers
Use
^<img src="index-(?![12]_)(\d+)_\d+\.(?:jpg|png)"\/><br>$
See regex proof. Use $1 as replacement.
EXPLANATION
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^ the beginning of the string
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<img src="index- '<img src="index-'
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(?! look ahead to see if there is not:
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[12] any character of: '1', '2'
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_ '_'
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) end of look-ahead
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( group and capture to \1:
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\d+ digits (0-9) (1 or more times (matching
the most amount possible))
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) end of \1
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_ '_'
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\d+ digits (0-9) (1 or more times (matching
the most amount possible))
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\. '.'
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(?: group, but do not capture:
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jpg 'jpg'
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| OR
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png 'png'
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) end of grouping
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" '"'
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\/ '/'
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><br> '><br>'
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$ before an optional \n, and the end of the
string