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PORegex: captures, groups, confusion
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copied!<p>I can't seem to figure out captures + groups in Regex (.net).</p> <p>Let's say I have the following input string, where each letter is actually a placeholder for more complex regex expression (so simple character exclusion won't work):</p> <pre><code>CBDAEDBCEFBCD </code></pre> <p>Or, more generically, here is a string pattern written in 'regex':</p> <pre><code>(C|B|D)*A(E*)(D|B|C)*(E*)F(B|C|D)* </code></pre> <p>There will only be one A and one F. I need to capture as individual 'captures' (or matches or groups) all instances of B, C, D (which in my app are more complex groups) that occur after A and before F. I also need A and F. I don't need E. And I don't need the C,B,D before the A or the B,C,D after the F.</p> <p>I would expect the correct result to be:</p> <pre><code>Groups["start"] (1 capture) = A Groups["content"] (3 captures) Captures[0] = D Captures[1] = B Captures[2] = C Groups["end"] (1 capture) = F </code></pre> <p>I tried a few feeble attempts but none of them worked.</p> <p>Only "incorrectly" captures the last C before EF in the sample string above (as well as correctly start = A, end = F)</p> <pre><code>(?<=(?<start>A)).+(?<content>B|C|D).+(?=(?<end>F)) </code></pre> <p>Same results as above (just added a + after (?B|C|D) )</p> <pre><code>(?<=(?<start>A)).+(?<content>B|C|D)+.+(?=(?<end>F)) </code></pre> <p>Got rid of look-around stuff... same result as above</p> <pre><code>(?<start>A).+(?<content>B|C|D)+.+(?<end>F) </code></pre> <p>And then my good-for-nothing brain went on strike.</p> <p>So, what's the right way to approach this? Are look-arounds really needed for this or not?</p> <p>Thanks!</p>

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