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copied!<p>When using <code>typeof</code> in javascript, it's generally a good idea to compare the results with a triple equals comparator So instead of using <code>!=</code> use <code>!==</code></p> <p>Also in javascript, if you pass an object whose value is <code>undefined</code> into a conditional statement it will evaluate to false. <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Boolean" rel="nofollow">If value is omitted or is 0, -0, null, false, NaN, undefined, or the empty string (""), the object has an initial value of false.</a> This means that you could rewrite the above as follows unless you're specifically looking for the value to be exactly <code>undefined</code>:</p> <pre><code>function getTotal(){ // If optA does not exist, create the variable and assign it if (!optA) { var optA = getDDValue("optA"); // Otherwise it exists, now set it to "0" pleaseandthankyou :) } else { optA = "0"; } ... } </code></pre> <p><strong>EDIT :</strong> Based on your replies to the above answer I think this might help: The variable <code>element</code> is null. That means that no elements could not be found with an id of <code>elementID</code> and so it was set to null. Because it is null, it has no property <code>options</code>. Check to make sure that there actually is a DOM element with the id attribute equal to whatever you pass in as <code>elementID</code>.</p> <pre><code>function getDDValue(elementID){ var element = document.getElementById(elementID); var value; // if the element exists if(element){ value = element.options[element.selectedIndex].value; }else{ value = 0; } console.log(value); return parseFloat(value); } </code></pre>

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