how to get the value of checksum in php header
<p>I have a header in php which contains a link like</p>

<pre><code>&lt;?php
header("Location: "."https://abc.com/ppp/purchase.do?version=3.0&amp;".
    "merchant_id=&lt;23255&gt;&amp;merchant_site_id&lt;21312&gt;&amp;total_amount=&lt;69.99&gt;&amp;".
    "currency=&lt;USD&gt;&amp;item_name_1=&lt;incidentsupporttier1&gt;&amp;item_amount_1=&lt;1&gt;&amp;".
    "time_stamp=&lt;2010-06-14.14:34:33&gt;&amp;**checksum=&lt;calculated_checksum&gt;**");
?&gt;
</code></pre>

<p>when i run this page the value of checksum is calculated and the link is opened</p>

<p>now how checksum is calculated?
calculated_checksum=md5(abc);</p>

<p>md5 is an algorithm which calculates the value of checksum based on certain values inside the bracket.</p>

<p>now i want to know how can i pass the value of checksum in the header url  </p>
