I'm using JSLint to go through JavaScript, and it's returning many suggestions to replace == (two equals signs) with === (three equals signs) when doing things like comparing idSele_UNVEHtype.value.
Novice JavaScript developers need to know that the "not not" operator is using implicitly the original loose comparison method instead of the exact === or !== operators and also the hidden cast operation that is happening behind the scenes and I show it in the example I provide.
Javascript does have types; and in any case, how is the dollar sign even related to that? It's just a character that happens to be a legal identifier in Javascript.
A valid JavaScript identifier shuold must start with a letter, underscore (_), or dollar sign ($); subsequent characters can also be digits (0-9). Because JavaScript is case sensitive, letters include the characters "A" through "Z" (uppercase) and the characters "a" through "z" (lowercase).
Related to Is there a "null coalescing" operator in JavaScript? - JavaScript now has a ?? operator which I see in use more frequently. Previously most JavaScript code used ||. let userAge =
In all other cases, you're safe to use ==. Not only is it safe, but in many cases it simplifies your code in a way that improves readability. I still recommend Crockford's talk for developers who don't want to invest the time to really understand Javascript—it's good advice for a developer who only occasionally works in Javascript.
var linkElement = document.getElementById("BackButton"); var loc_array = document.location.href.split('/'); var newT = document.createTextNode(unescape(capWords(loc_array[loc_array.length-2]))); linkElement.appendChild(newT); Currently it takes the second to last item in the array from the URL. However, I want to do a check for the last item in the array to be "index.html" and if so, grab the ...
JavaScript allows upper- and lower-case letters (in a wide variety of scripts, not just English), numbers (but not at the first character), $, _, and others.¹ Prototype, jQuery, and most javascript libraries use the $ as the primary base object (or function).
Note: In general, extending the built-in prototypes in JavaScript is generally not recommended. I am providing as extensions on the String prototype simply for purposes of illustration, showing different implementations of a hypothetical standard method on the String built-in prototype.
