What is x7f in php?
<p>What is <strong>x7f</strong> and <strong>xff</strong> in php?</p>

<p>Is it hexa or octal values?</p>

<p>EDIT:</p>

<p>It is given in PHP 5.3 manual that, as a regular expression, class name would be expressed as: <strong>[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*</strong>. </p>

<p>can any one help what is the meaning of <strong>\x7f-\xff</strong> in above regular expression?</p>
