How to make C# Regex work with "new line" characters in textfile?

Hello,

NOTE: I am a C# programmer - if you give a solution with UNIX or PERL formatting I won't know what to do with it. Please observe the forum I am asking this question in (C#). Thanks!

 I am writing a parsing module using regex's and ran across a snag: when my input contains new lines characters my regex stops working. I think best explaination is with code:



        [Test]
        public void ApplyStartAndStopAnchors()
        {
            string urlContent = "abcdefghijklmnopqrstuvwxyz";
            string regexString = "mno";
            string regexStartString = "def";
            string regexStopString = "stu";

            RegexGenerator generator =
                new RegexGenerator(new List<string>(), regexString, regexStartString, regexStopString, urlContent);

            generator.ApplyStartAndStopAnchors();
            Assert.AreEqual("ghijklmnopqr", generator.UrlContent); // PASSES
        }

And this example wouldn't be complete without generator.ApplyStartAndStopAnchors() (this being where I need your help)

        public void ApplyStartAndStopAnchors()
        {
            string subRegex = @"(?<=" + _regexStartString + ")" + "(.+)" + "(?=" + _regexStopString + ")";

            Regex r = new Regex(subRegex);

            Match m = r.Match(UrlContent);

            if (m.Success)
                UrlContent = m.Groups[1].Value;
        }


Now here's the catch, if I use multiline input:

Input text file: (MultiLineRegexTest.txt)
<start>
abcdefghij
klmnop
qrstuvw
xyz
<stop>

Which is just the English alphabet spread across 4 lines.

Now, when I read this input text file it contains new line characters. Here is a test showing the result:

        [Test]
        public void ApplyStartAndStopAnchorsOnTestFileWithMultipleLines()
        {
            FileStream fs = FileSupport.OpenFile(@"../../../Testfiles/MultiLineRegexTest.txt");
            string content = FileSupport.GetTextFileAsString(fs);

            string regexString = "mno";
            string regexStartString = "def";
            string regexStopString = "stu";

            RegexGenerator generator =
                new RegexGenerator(new List<string>(), regexString, regexStartString, regexStopString, content);

            generator.ApplyStartAndStopAnchors();
            Assert.AreEqual("ghijklmnopqr", generator.UrlContent); // FAILS
        }

And the output of the failing Assert.AreEqual statement is:

<start>
RegexGeneratorTestFixture.ApplyStartAndStopAnchorsOnTestFileWithMultipleLines : FailedNUnit.Framework.AssertionException:
String lengths differ.  Expected length=12, but was length=32.
Strings differ at index 0.

expected:<"ghijklmnopqr">
 but was:<"abcdefghij\r\nklmnop\r\nqrstuvw\r\nxyz">
-----------^
<stop>



Notice \r\n in the "but was" output? Those are the new line characters. They make it so my Regex in ApplyStartAndStopAnchors() doesn't work anymore.


Does anyone know how to fix this?

Much thanks,
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