match numbers not prefixed with specific word by Regex

Question

I want to extract the numbers that are not behind "A" by Regex.

For textA123text , none should be matched because 123 is behind A .

For textBC123text , 123 should be matched.

I found negative lookbehind like (?<!A)(\\d) does not work. It matches 23 in textA123text because 23 is behind 1 .

Is there any way to do this by using Regex?

Answer 1

In addition to using negative lookbehind for A , also negative lookbehind for \\d , to ensure that you're at the first character in a number, which is not preceeded by A :

(?<![A\d])\d+

https://regex101.com/r/jhWM30/1

Answer 2

当然，只需在您的后置断言中添加\\d即可：

(?<![A\d])(\d+)