Updating a Work Order via script

I am trying to change the components on a Work Order via script.  When I run the following code through the console, it works as expected:

var workOrder = <em>record</em>.load({ type: <em>record</em>.Type.WORK_ORDER, id: 213, isDynamic: true });    while (workOrder.getLineCount({ sublistId: 'item' }) &amp;gt; 0) {       workOrder.removeLine({ sublistId: 'item', line: 0 });  }    var allComponents = [];  allComponents.<strong>push</strong>({ item: 51, quantity: 800 });  allComponents.<strong>push</strong>({ item: 65, quantity: 200 });    for (var j = 0; j &amp;lt; allComponents.length; j++) {       workOrder.selectLine({ sublistId: 'item', line: j });       workOrder.setCurrentSublistValue({ sublistId: 'item', fieldId: 'item', value: allComponents[j].item });       workOrder.setCurrentSublistValue({ sublistId: 'item', fieldId: 'quantity', value: allComponents[j].quantity });       workOrder.commitLine({ sublistId: 'item' });  }    workOrder.save();