Help: How do I get the regex for this page number?

example.com/photos/gray?pg=2

And that pg=2 can be any number.

What will the full url look like and what will only the ?pg=X look like?

The software I need it for has this information: Addresses containing any of the below strings will be downloaded. All of the below strings are treated as regex

I have tried \?pg=.* and it didn't work.

What am I missing?

CodePudding user response：

The reason your regex did not work is that you did not escape the ? character with a backslash. In regex, the ? is also used for a lazy selection.
A working regex would be:

\?pg=([0-9]*)

But for parsing URLs it is not recommended to use regex and an URL parser should be used instead.

CodePudding user response：

1. If you want to get a string like ?pg=X then you can use \?pg=\d*.

• \d* - matches any number.

regex101.com

2. If you want to get only page number (an integer), you can use this regex: (?<=pg=)\d*

regex101.com

• (?<=pg=) is a positive lookbehind, it searches everything after the string pg=.
• \d* - matches any number.

You didn't mention a flavour for your regex, but positive lookbehind construction works in all given flavours at regex101.com.