正则表达式错误，匹配数字

Question

I have a string 00000001001300000708303939313833313932E2

so, I want to match everything between 708 & E2 ..

So I wrote:

(?<=708)(.*\\n?)(?=E2) - tested in RegExr (it's working)

Now, from that result 303939313833313932 match to get result (every second number):

099183192

How ?

Answer 1

To match everything between 708 and E2 , use:

708(\d+)

if you are sure that there will be only digits. Otherwise try with:

708(.*?)E2

To match every second digit from 303939313833313932 , use:

(?:\d(\d))+

Answer 2

use a global replace:

find: \d(\d)
replace: $1

Answer 3

Are you expecting a regular expression answer to this?

You are perhaps better off doing this using string operations in whatever programming language you're using. If you have text = "abcdefghi..." then do output = text[0] + text[2] + text[4]... in a loop, until you run out of characters.

You haven't specified a programming language, but in Python I would do something like:

>>> text = "abcdefghjiklmnop"
>>> for n, char in enumerate(text):
...   if n % 2 == 0: #every second char
...     print char
... 
a
c
e
g
j
k
m
o