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POTransfer javascript variable to php using hidden forms?
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  1. POTransfer javascript variable to php using hidden forms?
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    copied!<p>I have a form on my page that asks users to enter in their height/weight and it calculates their BMI and stores it in a database. I am hung up on how I transfer the javascript variable to a php variable. I understand I have to use hidden forms but I can't seem to figure out how they work. </p> <p>here is my code</p> <pre><code>&lt;?php include "base.php"; ?&gt; &lt;?php session_start (); ?&gt; &lt;!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"&gt; &lt;html xmlns="http://www.w3.org/1999/xhtml"&gt; &lt;head&gt; &lt;title&gt;BMI&lt;/title&gt; &lt;/head&gt; &lt;body&gt; &lt;form id="bmi" action="main.php" method="post"&gt; &lt;p&gt;Enter your height(in inches):&lt;/p&gt;&lt;input type="text" id="height box" name="height box"&gt; &lt;p&gt;Enter your weight(in pounds):&lt;/p&gt;&lt;input type="text" id="weight box" name="weight box"&gt; &lt;input type="hidden" id="bmi" name="bmi"&gt; &lt;input type="button" value="Calculate" id="calc button" name="calc button" onClick="calc()"&gt; &lt;/input&gt; &lt;/form&gt; &lt;script type="text/javascript"&gt; function calc() { // get variables from textboxes var height=document.getElementById('height box').value; var weight=document.getElementById('weight box').value; var bmi=document.getElementById('bmi').value; // calculate BMI weight/=2.2; height/=39.37; BMI=Math.round(weight/(height*height)); &lt;/script&gt; &lt;?php //insert username, date, and bmi into the db $username = mysql_real_escape_string($_SESSION['Username']); $date = date('Y-m-d'); $bmi = mysql_real_escape_string($_POST['bmi']); mysql_query("INSERT INTO bmi (username, bmi, date) VALUES('".$username."', '".$bmi."', '".$date."')"); ?&gt; &lt;/body&gt; &lt;/html&gt; </code></pre> <p>base.php is just where I do my connect to the sql server and select the database stuff</p> <p>The javascript bmi variable does not seem to be transferring to the php $bmi variable. What is it I am doing wrong?</p>
 

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