What is the best and fastest way to extract substring from string?
<p>What is the best and most effective way to extract a string from a string? I will need this operation to be preforms thousands of times.</p>

<p>I have this string and I'd like to extract the URL. The URL is always after the "url=" substring until the end of the string. For example:  </p>

<pre><code>http://foo.com/fooimage.php?d=AQA4GxxxpcDPnw&amp;w=130&amp;h=130&amp;url=http00253A00252F00252Fi1.img.com00252Fvi00252FpV4Taseyww00252Fhslt.jpg
</code></pre>

<p>and I need to extract the </p>

<pre><code>http00253A00252F00252Fi1.img.com00252Fvi00252FpV4Taseyww00252Fhslt.jpg
</code></pre>

<p>I want to avoid using split and such.</p>
