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copied!<p>Alright so I'm going to try to address all the parts of your question in my answer.</p> <p>As Ian had mentioned, there is a syntax error in your <code>for</code> statement.</p> <p>On second thought I'll give the code then do the explanation. I have included the entire HTML document for purposes of clarity:</p> <pre><code><!DOCTYPE html> <html lang=en-CA> <meta charset=utf-8> <title>JavaScript in multi-select</title> <script> function selectItems(stringFromDB) { 'use strict'; var select = document.getElementById("multiselectid"), stringArray = stringFromDB.split(","), count = 0, i; for(count = 0; count < stringArray.length; count += 1) { for(i = 0; i < select.options.length; i += 1) { if(select.options[i].value === stringArray[count]) { select.options[i].selected = true; } } } } window.addEventListener('load', function() { 'use strict'; // The "string from DB" would be the parameter here selectItems( 'hockey,volleyball,football'); }, false); </script> <body> <div> <select id='multiselectid' multiple> <option value="hockey">Hockey</option> <option value="golf">Golf</option> <option value="volleyball">Volleyball</option> <option value="football">Football</option> </select> </div> </code></pre> <p>Now for the explanation.</p> <ol> <li><p>Instead of using the traditional <code>onload</code> event attribute on the body element to run the script on page load (as you had wanted), I attached an event handler with the event <code>load</code> to the <code>window</code> DOM element. Event handlers are more useful as they help separate the JavaScript from the HTML (and many other reasons). You can read more about event handlers here: <a href="https://developer.mozilla.org/en-US/docs/DOM/element.addEventListener" rel="nofollow">https://developer.mozilla.org/en-US/docs/DOM/element.addEventListener</a></p></li> <li><p>In the function <code>selectItems()</code>, I have put all of the variables onto one declaration to keep the code clean.</p> <p><strike>3. To avoid potential issues with arrays, I have called the variable <code>stringArray</code> instead. <code>array</code> is a reserved word in JavaScript and could cause issues with some browsers, although I'm not completely sure which ones (if any).</strike></p></li> <li><p>ALWAYS, ALWAYS, ALWAYS use <code>===</code> instead of <code>==</code>. That way you are sure the comparison is strict and correct (i.e. both things being compared are of the same type, in this case: strings).</p></li> <li><p>It is a good idea to force the handling of your JavaScript functions in strict mode by using <code>'use strict;'</code>. This way the browser will stop (and throw exceptions) if it detects something that is not allowed, and thus allowing you to write better JavaScript code.</p></li> </ol> <p>Hope this helped, feel free to ask more questions if you're still confused!</p>

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