Check if a string contains numbers and letters
<p>Hey guys I want to find a way to detect if a string contains both numbers and letters. For example if this string was loaded: "PncC1KECj4pPVW" It would be written to a text file because it contains both. However if the string was "qdEQ" it would not, because it only contains letters. Is there a method to do this? </p>

<p>I was trying to use</p>

<pre><code>$string = PREG_REPLACE("/[^0-9a-zA-Z]/i", '', $buffer);
</code></pre>

<p>But ti didn't work.</p>

<p>Any help would be appreciated.</p>
