split and get value after string in consolidated value using c#

Question

I want to get the value from the List<string> which contains different format as below.

Formats:

var fieldValue =  { 
      "00 1234567 89 EXT 098", 
      "001 234 56 789 EX 0987",  
      "0 0123456789 EXTEN 09",
      "00123456789 EXTENSION0987",
      "00123456789E098987" 
}

Among all these values, I want to get the value ('098', '0987', '09', '0987', '098987') after string such as 'EXT', 'EX', 'EXTEN', 'EXTENSION', 'E'

The string may be differ in each value, so that I confused to apply condition to get the values after that.

Also I am unable to split this using <space> since it may contain in some values.

Please advice me to get the required values. Thanks in advance,

Answer 1

We can try doing a regex replacement on ^.*?(?=\\d+$) and replace with empty string:

string input = "00123456789E098987";
string output = Regex.Replace(input, "^.*?(?=\\d+$)", "");
Console.WriteLine(input);
Console.WriteLine(output);

This prints:

00123456789E098987
098987

Note: In the case of an input which does not end in at least one digit, the above logic would just return that original input. Ie 123ABC remains as that.