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copied!<p>Your approach is interesting but very inefficient even once corrected. An efficient implementation of the wildcard matching algorithm uses an extension of the <a href="http://en.wikipedia.org/wiki/Bitap_algorithm" rel="noreferrer"><strong>shift-or algorithm</strong></a> (according to Wikipedia also called “bitap” by some sources, but I’ve never read that myself).</p> <p>The only change to the conventional shift-or algorithm is in the preprocessing: For each <code>*</code> that you encounter in the pattern, enable <em>all</em> characters in the alphabet at this position.</p> <p>If you want to correct your own algorithm, then replace the <code>Contains</code> call by <code>IndexOf</code>, and supply the position where it should start searching – namely, after the previous match. This will work for most cases, but it will perform a non-greedy search which might fail in some circumstances. An exhaustive search will necessarily backtrack. As I said, that’s inefficient, and the shift-or algorithm doesn’t suffer from this shortcoming.</p> <p><strong>But all of this is unnecessary</strong> since VB already provides the necessary operator: <strong><code>Like</code></strong></p> <pre><code>If fullString Like wildcardString Then ' Yep, matches. End If </code></pre> <hr> <p>A note on style:</p> <p>Always initialise variables when you declare them, do not separate declaration and initialisation needlessly.</p> <p>That is, write</p> <pre><code>Dim stringParts As String() = wildcardString.Split("*") ' or, with Option Infer On: Dim stringParts = wildcardString.Split("*") </code></pre> <p>Furthermore, it makes no sense to compare a Boolean with a literal (<code>If X = False</code> …). Just write</p> <pre><code>If fullString.Contains(str) Then </code></pre>

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