// Finding a specific line item in SuiteScript 2.0...
require(["N/record"], function (r) {
var rec = r.load({
"type": r.Type.SALES_ORDER,
"id": 123
});
// Find the line that contains item 777
var index = rec.findSublistLineWithValue({"sublistId": "item", "fieldId": "item", "value": 777});
// find returns -1 if the item isn't found
if (index > -1) {
// we found it on line "index"
} else {
// item 777 is not in the list
}
});