using System;
using System.Text.RegularExpressions;
public class Example
{
public static void Main()
{
string pattern = @"^!*(?P<title>[A-Za-z0-9].+?)(?:\s+(?P<isbn>[0-9]{10}))?\s+by\s+(?P<author>[A-Z0-9][^(]+)(?=\s\()";
string substitution = @"\3";
string input = @"!!Mixed Fortunes - An Economic History of China Russia and the West 0198703635 by Vladimir Popov (Jun 17, 2014 4_1).pdf
!Mixed Fortunes - An Economic History of China Russia and the West 0198703635 by Vladimir Popov (Jun 17, 2014 4_1).pdf
Mixed Fortunes - An Economic History of China Russia and the West 0198703635 by Vladimir Popov (Jun 17, 2014 4_1).pdf
!!Mixed Fortunes - An Economic History of China Russia and the West by Vladimir Popov (Jun 17, 2014 4_1).pdf
!!Mixed Fortunes - An Economic History of China Russia and the West by 1 Vladimir Popov (Jun 17, 2014 4_1).pdf";
RegexOptions options = RegexOptions.Multiline;
Regex regex = new Regex(pattern, options);
string result = regex.Replace(input, substitution);
}
}
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for C#, please visit: https://msdn.microsoft.com/en-us/library/system.text.regularexpressions.regex(v=vs.110).aspx