Run PHP echoed Javascript

Question

I am just getting into the world of PHP, Javascript and HTML and would like some help from the community regarding the following code. Basically I want to pass variables plucked from a ODBC_connection by PHP into textboxes. Lines 1-3 were for me to test to get the box to update which it does but anything echoed by PHP does not run. I am completely new to this so I realize I must be missing something trivial.

I welcome any suggestions or comments about what I can do to fix this or what I can do better in general. Thank you.

<script type='text/javascript'>
document.getElementById('modeltxt').value = "test2";
</script>
<?php
echo "<script type='text/javascript'>";
echo "document.getElementById('modeltxt').value =\"TEST3\";";  
echo "document.getElementById('customertxt').value = $customer;";  
echo "document.getElementById('endusertxt').value = $enduser;";  
echo "document.getElementById(dongletxt').value = $dongle;";
echo "document.getElementById('shipdatetxt').value = $shipdate;";
echo "document.getElementById('chasistypetxt').value = $chasistype;";
echo "document.getElementById('chasisnumbertxt').value = $chasisnumber;";  
echo "document.getElementById('opsystxt').value = $opsys;";
echo "document.getElementById('dvd1txt').value = $dvd1;";  
echo "document.getElementById('dvd2txt').value = $dvd2;";
echo "document.getElementById('storagetxt').value = $storage;";  
echo "document.getElementById('nodrivetxt').value = $nodrive;";
echo "document.getElementById('drivesizetxt').value = $drivesize;";  
echo "document.getElementById('interface1txt').value = $interface1;";  
echo "document.getElementById('interface2txt').value = $interface2;";  
echo "document.getElementById('interface3txt').value = $interface3;";  
echo "document.getElementById('interface4txt').value = $interface4;";  
echo "document.getElementById('interface5txt').value = $interface5;";  
echo "document.getElementById('interface6txt').value = $interface6;";  
echo "document.getElementById('commentstxt').value = $comments;";
echo "document.getElementById('warrantyexptxt').value = $warrantyexp;";
echo "document.getElementById('extendedwarrantytxt').value = $extwarexp;";  
echo "document.getElementById('onsitetxt').value = $onsite;";
echo "document.getElementById('sqlversiontxt').value = $sqlversion;"; 
echo "<\script>";

Answer 1

You can create dynamics JS using the below

Define Content-Type on the top of your .js.php file:
<?
header('Content-Type: application/javascript');
// Write your php code
?>
 and call the js file like this ..

<script type="application/javascript" src="JS_PATH/name-of-file.js.php"></script>

and if you want to use inline php values, you can write like this

<script type="application/javascript">
document.getElementById('modeltxt').value = "<?php echo $dummy_value ?>";
</script>

Answer 2

No need to do this. You can simply use javascript inside php as below :-

As you mention in your question

Basically I want to pass variables plucked from a ODBC_connection by PHP into textboxes.

<?php
  // Php block of code

?>
<script type="text/javscript">
  document.getElementById('modeltxt').value = "TEST3";
  document.getElementById('customertxt').value = "<?php echo $customer;?>"; 
   ......
   ....
   ...
</script>
<?php

// Another block of code

?>