In protractor, there are, basically, 3 ways to check if an element is present:
var elm = element(by.id(\"myid\")); browser.isElementPresent(elm); elm.isPres
You can check whether the element is present or not by using the isPresent function.
So, your code would be something like:
var myElement = element(by.css('.elementClass')); expect(myElement.isPresent()).toBeFalsy();
Here is the protractor docs for the isPresent function.