Match number between 2 date - regex

Question

I got a text and I need to extract a number that is between 2 dates. I can't show the full text so I will only use the part I need, but keep in mint it's part of a bigger text.
12/14/2020 355345 12/14/2020
From that, I need to get '355345', I currently don't have anything to show of what I was doing because I was working on getting the text before a sentence, until I realized it the only place where the number is between 2 dates.
Thanks!

Answer 1

Here's a snippet that might help:
Suppose the input is this:
Imports System.Text.RegularExpressions
'...
Dim input As New StringBuilder
input.AppendLine("12/14/2020 355345 12/14/2020")
input.AppendLine("12/13/2020 425345 12/13/2020")
input.AppendLine("12/20/2020 93488557 12/20/2020")
input.AppendLine("12/21/2020 4 12/21/2020")
input.AppendLine("12/20/2020 3443 12/20/2020")
'...
Use RegEx to extract the numbers between the two dates as follows:
Dim patt = "(\d+\/\d+\/\d+)\s?(\d+)\s?(\d+\/\d+\/\d+)"
For Each m In Regex.
Matches(input.ToString, patt, RegexOptions.Multiline).
Cast(Of Match)
Console.WriteLine(m.Groups(2).Value)
Next
This will capture three groups. Example for the first match:
m.Groups(1).Value : 12/14/202 the first date.
m.Groups(2).Value : 355345 the number in between.
m.Groups(3).Value : 12/14/2020 the second date.
If you have no use for the captured dates, then no need to get theme grouped and use the following pattern instead:
Dim patt = "\d+\/\d+\/\d+\s?(\d+)\s?\d+\/\d+\/\d+"
For Each m In Regex.
Matches(input.ToString, patt, RegexOptions.Multiline).
Cast(Of Match)
Console.WriteLine(m.Groups(1).Value)
Next
And you will get the number between the two dates in Group 1.
The output of both is:
355345
425345
93488557
4
3443
regex101
Also, using the quantifiers in RegEx patterns is a good idea as Mr. #AndrewMorton mentioned in his appreciated comments, and that to skip any possible things like 1234/239994/2293 in the input:
Dim patt = "\d{1,2}/\d{1,2}/\d{4}\s(\d{1,})\s\d{1,2}/\d{1,2}/\d{4}"
For Each m In Regex.
Matches(input.ToString, patt, RegexOptions.Multiline).
Cast(Of Match)
Console.WriteLine(m.Groups(1).Value)
Next
The quantifiers-way test is here.

Answer 2

If you can safely check for numbers and slashes, then a pattern like this should work:
\d\d/\d\d/\d\d\d\d +(\d+) +\d\d/\d\d/\d\d\d\d
...where capture group 1 would hold the number being sought. If you need to validate that the values are actually dates, well... you can do it with regex to a degree, but the pattern becomes very difficult to read.