Question

Consider the following input:
BEGINsomeotherstuffEND

I’m trying to write a regular expression to replace BEGIN and END but only if they both exist.

I got as far as:

(^BEGIN|END$)

Using the following c# code to then perform my string replacement:

private const string Pattern = "(^guid'|'$)";
private static readonly Regex myRegex = new Regex(Pattern, RegexOptions.Compiled | RegexOptions.CultureInvariant | RegexOptions.ExplicitCapture | RegexOptions.Singleline | RegexOptions.IgnoreCase);
var newValue = myRegex.Replace(input, string.empty);

But unfortunately that matches either of those – not only when they both exist.

I also tried:

^BEGIN.+END$

But that captures the entire string and so the whole string will be replaced.

That’s about as far as my Regular Expression knowledge goes.

Help!

Answer 1

How about using this:

^BEGIN(.*)END$

And then replace the entire string with just the part that was in-between:

var match = myRegex.Match(input);
var newValue = match.Success ? match.Groups(1).Value : input;