I have the following JavaScript object: Is there a way to check if a key exists in the array, similar to this? does not work. Do I have to iterate through the obj like this? Answer Use the in operator: Sidenote: What you got there, is actually no jQuery object, but just a plain JavaScript Object.
Author: admin@master
`binding.pry` for javascript console?
In Ruby, I can type binding.pry anywhere in my code and at that point of execution my console will enter a REPL where I have access to all local variables, can make changes, and execute any arbitrary code. Example: When I run it: This is an incredible tool in debugging, especially for situations that require …
Attempting to make enter button ‘clickable’
I want to make a ‘search’ button clickable upon clicking enter. This is my html: This is the JavaScript I am using: I am however getting an error ‘Uncaught TypeError:Cannot call method click of nul’ Advice perhaps on why I get this error and is there a better alternative at achieving t…
Break for loop from inside of switch case in Javascript
What command I must use, to get out of the for loop, also from //code inside jump direct to //code after Answer Unfortunately, Javascript doesn’t have allow breaking through multiple levels. The easiest way to do this is to leverage the power of the return statement by creating an anonymous function: Th…
Button background color toggle
I have been trying to toggle the background-color property of a button onclick but the color only changes once and does not toggle back and forth. Below is the code. Answer The problem you’re having is that the background-color of an element is reported differently in browsers, either rgb, rgba (with, o…
form submit jquery v javascript difference
in javascript this works fine and the validateForm function fires but why doesnt a similar implementation of the same code in jquery not work? This is what I would like to do after reading http://api.jquery.com/submit/ the following code works why does the submit method require a function to wrap around the c…
How to remove the extra spaces in a string?
What function will turn this contains spaces into this contains spaces using javascript? I’ve tried the following, using similar SO questions, but could not get this to work. Is there a simple pure javascript way to accomplish this? Answer You’re close. Remember that replace replaces the found tex…
HTML5 Remove previous drawn object in canvas
I have a polygon object (say a car) drawn inside a HTML5 canvas with help of methods moveTo and lineTo. I want to repeatedly draw that object at different positions in the canvas (simulating a moving object). My problem is that the previous drawn object is not getting cleared. Instead, multiple images are dra…
How to show zoom level on openlayers (js/html file only)?
looking for some help on this. I know it is something along the lines of Looking to add a div for the zoom status also: or what would be the best approach? If someone could offer some insight, it would be appreciated. Couldn’t find the answer in the documentation. Answer I don’t believe in the cur…
Javascript closures on heap or stack?
Where does JavaScript (according to the standard) store closures: heap or stack? Is there a third explicit place for closures? Answer In the end it is an implementation detail of the runtime. See Phoenix link As to implementations, for storing local variables after the context is destroyed, the stack-based im…