using System;
using System.Text.RegularExpressions;
public class Example
{
public static void Main()
{
string pattern = @"^(?:[a-z]\)|\(\d+\))[^#]*?(?=\n\(\d\)|\Z|#|\n[a-z]\))";
string input = @"#1
(1) This is a test.
a) This is a subtest one.
b) And another one.
(2) A really cool test.
(3) Here is the problem, text for each numbered line is
supposed to be on a single line like in (1) and (2), but
the text often spans multiple lines of text.
(4) How can I match the multi-line entries and unwrap them to single lines?
#2
(1) This is a test.
a) This is a subtest one.
b) And another one.
(2) A really cool test.
(3) Here is the problem, text for each numbered line is
supposed to be on a single line like in (1) and (2), but
the text often spans multiple lines of text.
(4) How can I match the multi-line entries and unwrap them to single lines?
#3
(1) This is a test.
a) This is a subtest one.
b) And another one.
(2) A really cool test.
(3) Here is the problem, text for each numbered line is
supposed to be on a single line like in (1) and (2), but
the text often spans multiple lines of text.
(4) How can I match the multi-line entries and unwrap them to single lines?";
RegexOptions options = RegexOptions.Singleline | RegexOptions.Multiline;
foreach (Match m in Regex.Matches(input, pattern, options))
{
Console.WriteLine("'{0}' found at index {1}.", m.Value, m.Index);
}
}
}
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