Please help me to understand why the following code works: In the first line there is no new operator. As far as I know, a contructor in JavaScript is a function that initialize objects created by the operator new and they are not meant to return anything. Answer In general, if something is documented as being a constructor, use new
How to delay the .keyup() handler until the user stops typing?
I’ve got a search field. Right now it searches for every keyup. So if someone types “Windows”, it will make a search with AJAX for every keyup: “W”, “Wi”, “Win”, “Wind”, “Windo”, “Window”, “Windows”. I want to have a delay, so it only searches when the user stops typing for 200 ms. There is no option for this in the
How to determine whether an object has a given property in JavaScript
How can I determine whether an object x has a defined property y, regardless of the value of x.y? I’m currently using but that seems a bit clunky. Is there a better way? Answer Object has property: If you are testing for properties that are on the object itself (not a part of its prototype chain) you can use .hasOwnProperty():
Get size of mouse cursor in javascript
I need to determine the width and height of the current mouse cursor used on our webpage. I need to show a div right under the cursor, and possibly to the right of it. So I need to determine the offsets of my div from the exact pointer location, so the cursor do not cover up the div. The mechanism
Dynamically creating a textbox with a Javascript onkeyup event that takes parameters
What I have is a single textbox. If the user hits the maxlength of it, I want to create a new textbox and then change focus to it so they can continue typing. To accomplish this, I am trying to dynamically create textboxes that have an onkeyup event tied to them. To do this I am using document.createElement and the
Strip all non-numeric characters from string in JavaScript
Consider a non-DOM scenario where you’d want to remove all non-numeric characters from a string using JavaScript/ECMAScript. Any characters that are in range 0 – 9 should be kept. How would you achieve this in plain JavaScript? Please remember this is a non-DOM scenario, so jQuery and other solutions involving browser and keypress events aren’t suitable. Answer Use the string’s
How do I get just the visible text with jQuery (or Javascript)?
I have website that converts Japanese Kanji into Romaji (roman letters): and the output shows and hides with CSS what the user needs to see depending on their input criteria. For example: <div id=”output”><span class=”roman”>watashi</span> <span class=”english”>I</span></div> The interface allows the user to flip between and output of watashi or I depending on what they want to see. The CSS
Single quotes in string with jQuery ajax
I have run into a problem where the user enters data and if there are single quotes at all, the script errors out. What’s the best way to handle single quotes that users enter so it doesn’t interfere with the jquery/javascript? UPDATE: I’m sending it through ajax to a database. here is the data parameter for a json ajax call.
New line in JavaScript alert box
How do you put in a new line into a JavaScript alert box? Answer n will put a new line in – n being a control code for new line.
Is there an event that fires on changes to scrollHeight or scrollWidth in jQuery?
I’m using JQuery to design an application where the user can drag elements inside of a div that automatically adds scrollbars and expands the scrollHeight/scrollWidth as needed. I need to fire off an even when the scrollHeight and scrollWidth of the container div are changed. No, don’t want to use the scroll event because 1) scroll doesn’t get fired when