<div>
When you just want to replace all i's, then use string.Replace() instead. Simpler to use and faster.
</div>


<div>
Try this adjustment:<br />
<br />

<pre><code class="code-1 nolinks" id="code-20-43065819-1"><span>string input = &quot;i,for (EntityReader,i,new, (i), i&lt;i, ArrayList&lt;String&gt;()))i&quot;;</span>
<span>string pattern = &quot;([)(, -=&lt;&gt;+])(i)&quot;;</span>
<span>string outPut = Regex.Replace(input, pattern, &quot;$1j&quot;);</span>
</code></pre>
<hr />
»<b><i>bp</i></b>
</div>


Programmer

Misha

<div>
Thank you very match! In my case this Regex help me.<br />
<br />
gr8gonzo, can you post some links with good parser example?. My task is translation custom language like pascal to java, using C#.<br />
I know, that it sounds very strange..
</div>


<div>
Yikes, that's a complicated task, I'd suggest starting by checking out ANTLR. This is a pretty good article on generic parsing in C# and talks about different utilities, including ANTLR:<br />
<a href="https://tomassetti.me/parsing-in-csharp/" rel="ugc">https://tomassetti.me/parsing-in-csharp/</a><br />
<br />
Again, parsing any language is a complex task. Tools like ANTLR just make that task a little easier, but you have to have a good grasp of the language itself, ESPECIALLY if you're trying to convert code between 2 very different languages. Generally speaking, you should really stop and ask yourself how long it would take you to convert the code manually or rebuild from scratch. Automatic code conversion is prone to errors and often requires manual tweaking to get the final result to work, and even if it works, you might end up with performance issues.<br />
<br />
For example, let's say that in language #1 you have a code statement that queries a database. You convert it to language #2, and it works but the result is extremely slow and it crashes. Then it turns out that the converted code in language #2 has some unexpected overhead (e.g. opening a new database connection for each query), so it runs slower than the original and wastes resources.<br />
<br />
There are lots of possible scenarios like that, and you can generally avoid those kinds of problems by simply rebuilding from scratch, even though it might take longer.
</div>


<div>
<div class="content wysiwyg-content">
Hello! <br />
Please help me with regex in C#.<br />
<br />
I need to find &quot;i&quot; &nbsp;and replace it.<br />
<br />
My code<br />

<pre><code class="code-1 nolinks" id="code-10-29178760-1"><span> string input = &quot;i,for (EntityReader,i,new, (i), i&lt;i, ArrayList&lt;String&gt;()))i&quot;;</span>
<span> string pattern = &quot;[)(, -=&lt;&gt;+](i)&quot;;</span>
<span> string outPut = Regex.Replace(input, pattern, &quot;j&quot;);</span>
</code></pre>
<br />
Expected result is<br />
j,for (EntityReader,j,new, (j), j&lt;j, ArrayList&lt;String&gt;()))j<br />
<br />
But I get this: <br />
i,for (EntityReaderj,new, j),jj, ArrayList&lt;String&gt;()))i<br />
<br />
The symbol before &quot;i&quot; is lost. And I can not find first and last &quot;i&quot;.
</div>
</div>


Hello! 
Please help me with regex in C#.

I need to find "i"  and replace it.

My code
(CODE)

Expected result is
j,for (EntityReader,j,new, (j), j<j, ArrayList<String>()))j

But I get this: 
i,for (EntityReaderj,new, j),jj, ArrayList<String>()))i

The symbol before "i" is lost. And I can not find first and last "i".

C# Regex

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.

Regular Expressions

Programming includes both the specifics of the language you’re using, like Visual Basic, .NET, Java and others, but also the best practices in user experience and interfaces and the management of projects, version control and development. Other programming topics are related to web and cloud development and system and hardware programming.

Programming

C# is an object-oriented programming language created in conjunction with Microsoft’s .NET framework. Compilation is usually done into the Microsoft Intermediate Language (MSIL), which is then JIT-compiled to native code (and cached) during execution in the Common Language Runtime (CLR).