getElementValue function
Gets the element
value depending of identified type.
If the resolved value is null or empty, and def is not null,
it will return def
.
Implementation
String? getElementValue(Element element, [String? def]) {
String? value;
if (element.isA<HTMLInputElement>()) {
value = (element as HTMLInputElement).value;
} else {
value = getElementSRC(element);
}
return def != null && isEmptyObject(value) ? def : value;
}