How can I search for exact number through a file containing thousands of numbers?
<p>If we say that we have a text file containing order numbers or references (1 Number per 1 Line only) what is the best way to find/validate an input (number entered in form for example) against those numbers in a file?</p>

<p>Is there a simple idea to do it? Assume we have thousands of numbers to search through.</p>

<p>Thank you very much.</p>
