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<pre><code class="code-1 nolinks" id="code-20-40448637-1"><span>(?&lt;!\[)[a-zA-Z0-9](?=/)|(?&lt;!\])/[a-zA-Z0-9]</span>
</code></pre>
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** edit<br />
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Does &quot;preceded&quot; mean &quot;immediately preceded,&quot; or just &quot;preceded&quot;? Also, what programming language or text editor are you using?
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Thanks for responding. &nbsp;I mean immediately preceded and vb.net.
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Also, why would &quot;f/&quot; not satisfy the criteria? In other words, why does &quot;/d&quot; match, but &quot;f/&quot; does not?
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And I do not understand why &quot;/a&quot; matches. According to your criteria:<br />
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<blockquote>
 &quot;/&quot; &amp;&nbsp;an alphanumeric character when there isn't a &quot;]&quot; in front of it.
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But there most assuredly is a ] in front of the &quot;/a&quot;.
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That was a typo. f/ should also match. &nbsp;I'm sorry I was writing the example on the fly and missed my mistake.
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I'm doing a terrible job at explaining what I want. Sorry. &nbsp;A / and alphanumeric character or an alphanumeric character and / should always match unless they are inside a set of [].
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I made an edit to the above just now. Forgot one small character!
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I am using regexr.com to test the patterns out but your suggestion didn't match anything.
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Thanks for your help and suggestion. &nbsp;I will start using regexhero from now on.
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<div class="content wysiwyg-content">
I'm trying to create a regex that only matches when:<br />

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 An alphanumeric character that is not preceded by &quot;[&quot; but is followed by &quot;/&quot; 
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 and a &quot;/&quot; &amp;&nbsp;an alphanumeric character when there isn't a &quot;]&quot; in front of it.<br />
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for example:<br />
1[ts/tty]<b>/a</b>..[a/bravo] ntf<b>/d</b>t; <b>c/</b>[antenna/board] ---&gt; &nbsp;should match /a, /d and c/<br />
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So far I have (([^[])(-?\w)/) ---&gt; this matches /d and c/ but not /a. &nbsp;I have tried (([^[])(-?\w)/)|(/(-?\w)([<wbr />^]])) but can't get the character set of [^]] to match &quot;]&quot;.
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I'm trying to create a regex that only matches when:
 An alphanumeric character that is not preceded by "[" but is followed by "/" 
 and a "/" & an alphanumeric character when there isn't a "]" in front of it.

for example:
1[ts/tty]/a..[a/bravo] ntf/dt; c/[antenna/board] --->  should match /a, /d and c/

So far I have (([^[])(-?\w)/) ---> this matches /d and c/ but not /a.  I have tried (([^[])(-?\w)/)|(/(-?\w)([^]])) but can't get the character set of [^]] to match "]".

Can't get the character set of [^]] to match &quot;]&quot; in regex (([^[])(-?\w)/)|(/(-?\w)([^]])).

A regular expression ("regex") is a sequence of characters that define a search pattern, mainly for use in pattern matching with strings, or string matching, i.e. "find and replace"-like operations. Regular expression processors are found in several search engines, search and replace dialogs of several word processors and text editors, and in the command lines of text processing utilities, such as sed and AWK. Many programming languages provide regular expression capabilities, some built-in, for example Perl, JavaScript, Ruby, AWK, and Tcl, and others via a standard library, for example .NET languages, Java, Python and C++ (since C++11). Most other languages offer regular expressions via a library.

Can't get the character set of [^]] to match &quot;]&quot; in regex (([^[])(-?\w)/)|(/(-?\w)([^]])).

Can't get the character set of [^]] to match "]" in regex (([^[])(-?\w)/)|(/(-?\w)([^]])).