I am fairly new to javascript but I am an experienced php programmer. I have been parsing XML information using php, but my CPU usage has been too high recently due to this. I am trying to convert my scripts to javascript, but I am unsure how I can do this using javascript. I think that if I get started off, the rest will be easy.
One of my XML files is located at
Code:
http://ws.audioscrobbler.com/2.0/?method=user.getrecenttracks&user=bbcradio1&api_key=c910b0bc1e2d4e64964ebcd2d69c255c&limit=500
Basically I have been trying to grab the Name, Artist and large image of the most recent <track>.
I have a HTML form containing two text box controls in it and a submit button. When a user enters information in those two textboxes and click on submit, the information is sent to a function in Javascript. In the javascript, the information from those textboxes is stored in a javascript variable. The problem is as follows:When I am inputting string text in the html text boxes and in the javascript when I am trying to print those values, it is giving me out an error saying NaN. However when i input integer values in the text boxes it is printing those numbers. Is there a conversion that I have to do for the string to be printed. I am new to Javascript and need your help. This is a basic code of Javascript. Below is the code that I have.
<html> <script type = "text/javascript"> function square(form)
I have a team website that has several games for entertainment. One of the games is a javascript version of yahtzee. Can someone suggest a way, using javascript, to record a high score for the game instead of a high score for a particular user, session, or computer. Perhaps someone already has code written to do this.
We are currently trying to locate the JS that will allow us to implement a progression of low-res-->hi res load for the big background images we have on each page of our new web site.In other words, we have a ginormous photo in the background, and want to avail the browser a very lo res version of said photo while the big photo loads.I have a feeling this is a real rookie question, but still, if there is anyone that can advise I'd be super grateful
I am a back en developer and really don't understand event driven/front end development so if I use newbie terms or make no sense please bare with me. Could someone point me to some tutorials on how I might render something if and only the local machine has good processing power/ram. I am going to be rendering some stuff which will require quite a lot of processing power on the local side. Just a threshold thing really nothing predictive or anything just if ram is more than 1GB and processor faster than a P4 or something like that.
I am implementing a fairly large Javascript file that has many if/than's that decide whether to load new content into div's. I have noticed this is causing high client side CPU utilization. Is there any better way to do this besides having the example script below repeated many times... i need to keep CPU usage down.
Code: <script> $(document).ready(function() { //ajaxTime.php is called every second to get time from server
The jQuery library is definitely very useful for those who have development background experiences but don't have the time to learn Javascript in it's true nature. I've played with it on and off, on a few smaller sites I manage, and the outcome was truly amazing. I don't know Javascript at all, aside from the basics and I was able to create a very fun and fast UI very quickly for my visitors. I wonder though; Does the jQuery library hold up efficiency for larger sites?
I currently manage a site with over 1.6 million post, averaging around 15,000 post per day this month. With me not having the time to really learn Javascript and I don't have much of a budget to hire someone to do the work I want yet, it would seem logical to use jQuery if I already know how to use it, right? I just worry, with the growth rate for the site at it's all time high, I'm afraid that jQuery will do more bad then good.
Are there any high traffic sites successfully using jQuery that you know about? has anyone experimented with jQuery on their high traffic sites? Would it seems more sensible to hire someone to do the Javascript work?
I'm working on an interactive website where the user can change the font attributes of the text within the page they're reading. Is there a way to bind, for example, bold tags around a snippet of text the user has high-lighted? What I mean (if that wasn't clear) is if the user is reading through the text on the page and drags their mouse over a piece of text then clicks a button and it turns bold, much like a rich text editor would work, is this possible to do?
I am trying to see if the following can be achieved using Jquery I need to create a thumbnail gallery, where when a user hovers over any thumbnail image they would get an option to download the image either in High or Low resolution. Something like how you see in the below mockup.
The question has to do with the use of popup windows in a web page. I have heard that popup windows should be avoided; due to use of popup blockers and browser that do not process javascript.
Is the use of popup windows bad design? Will it severly reduce the usage of our web page?
Note, The popup windows are created using only onClick events, not onLoad or onClose events. Do popup blockers make any distinction between the two?
I'm really hoping someone out there can help me with an unusual, frustrating XP problem that I just can't seem to fix.
When certain web pages are opened with my Internet Explorer 6, it causes the CPU to jump up to 100% usage, and my computer comes to almost a halt. The culprit, according to Task Manager, is always IEXPLORE.EXE, or at least one of the IEXPLORE.EXEs if there are multiple instances.
I've noticed a common thread to virtually all sites that cause the CPU to run at 100% -- Javascript. Pages containing Javascript are virtually always the problem. Examples:
1) almost all pop up windows 2) Yahoo! Mail 3) Match.com Searches 4) All Music Guide
I'm not a computer expert at all, so I've only done what I can think of, or what has been suggested to me. I've checked/removed spyware/malware with multiple pieces of software (Spybot, etc.) I've defragged. I've checked for viruses using both NAV and PC-cillin. I've used my System Mechanic program to go through almost all fixes/maintanance/optimizers. The only thing i haven't been able to do is Windows ChkDisk, because it gets stuck every time I try to use it.
I'm used to C/C++ where if you "new" something you really need to "delete" it later. Is that also true in javascript? if i do "mydate = new date();" in a function and dont "delete mydate" when the function exits do i have a memory leak or other trouble brewing?
ie: function MyFn() { var mydate;
mydate = new date(); }
does the above function present a problem (what if its called over and over and over etc)? or is the allocation automaticaly freed on function exit?
I'm writing a very complex javascript application and I'd like memory usage to be as low as possible, so I've got a question about objects.
I'm using jQuery and my code is a bunch of jQuery plugins that interact with eachother. Will there be a difference in memory usage if I declare functions like this:
I haven't written anything in javascript as complex as I'm about to write, so I never worked with objects. As far as I understand, $.fn.whatever will add function to prototype, while $.whatever will add function only to one entry of jQuery object.
So question comes down to this: when jQuery object is being created, are functions in it being copied (meaning increase in memory usage) or does javascript only make references (meaning no significant increase in memory usage) to one main entry of that function in prototype?
I noticed that Apple updated their website. In this thread I asked what people's thoughts on it were, but one of the main things I noticed in the mac and or the iPod pages is that the content elegantly spreads outward form the centre and fades in when the document is loaded.
So, I have a few questions, How would one do this? I know the fading can be done with jQuery, but what about the fanning-out form the centre? And also how the fade order is from top to bottom not what loads first is one of the aspects that makes it elegant, I believe. How would one do this?
My original fiddle for a solution used a separate callback function which just called def.resolve().However I then remembered that I've seen other code simply pass "def.resolve" as a callback in its own right. I tried this instead, and it works (see http://jsfiddle.net/Nyg4y/3/).This got me wondering - how does this work? As I understand it for this to work at all the value 'def.resolve' must be specific to 'def'.This suggests that it is actually a (reference to a) closure holding a reference to 'def' in its scope. Is my understanding correct, and if so is this behaviour guaranteed?
I have a simple page and a javascript that measure the time the user has spent on a page and I want that variable to pass as a link to another page (php). I'm stuck (rookie) with how to actually pass that on in the link.Here's my code:
I am using this code load a file from server to display in to a div.
Code JavaScript: function getHTTPObject() { var xhr = false; if (window.XMLHttpRequest) { xhr = new XMLHttpRequest(); [Code]...
I want to use the same script but apply for a button, clicking the button, a file called from server will display in the div "ask_seller". Since button has no href attribute, I don't know how to name the file that going to be called(or I don't know what is the usage in this case)
I have a really long application so i'm trying to minimiza cpu/memory usage,with each function, therefore I have a few simple questions.
1. on elements added after the page has been loaded,is there a difference between putting "onclick" inside the element tag or using jquery's delegate like the following example?
2. does it make a big difference selecting an element with a full path like (#body #contentdiv #userstbl td.example)or just typing (.example) ?
3. I have 2 arrays of objects, both objects has an id attribute, one of then objects are the images on the page, the second one is an ajax result with updated images.will it be better to first loop threw both objects just to create new arrays with just the id's instead of looping the threw those big objects? like this:
Code: if (data.online) var online_length = data.online.length; else[code]..........
Issue: Received project from previous developer who left. The working URL generates a table chart using Javascript after you have entered a valid address/zip code. I haven't been able to determine why I can't get the "schoolfinder-business.asp" URL to generate a table chart using Javascript. I believe the issue is related to something in the function GetDirections, but I cannot pinpoint the issue.
Is there a way to check the page for invalid usage (e.g. text boxes using .text which doesnt exist)? I originally thought I could use the .data("events") but then realize that .text and .val isn't an event which is pretty obvious but I'm stuck now. I already know my selector is $('input[type="text"]') but is there any way to see if anywhere on the page is improperly calling .text()?
My AJAX script runs fine on IE and Opera, but in firefox memory usage raises exponently (sript processes text, more text I use, more memory needed... when I use up to 1000 words, it takes 2 GB RAM on Firefox, while few mb on IE and Opera only).
