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Hey all! I am doing my advanced higher computing in my last year of school and as part of the course we have to complete a project of our choosing. I have chosen to do an Online Course Choice Selection system which basically lets you pick your subjects for school online compared to the old paper system that schools across Scotland currently do. However I have come to a problem. I have a working Log In system however I think i have done it a crazy way. I have it so when you press the submit it redirects to a PHP file does the MySQL work then redirects back to the next javascript page. However thats not the problem as that all works fine. My issue is that I have created a page that displays all of the information of everyone who has used the system to the admin. To do this I need to save get all the data from MySQL using PHP then i have set up the javascript so it takes in lists and displays them and i cant do the redirecting because i cant have it send hundreds of cookies. So basically i want to know how i can make a page read data from the MySQL server then output it to a list i can read in Javascript. Sorry for the long post i just thought it would make more sense if I gave some background. Any help will be appreciated. Thanks Gavin

Here's Part one. XMLHttpRequest Response What is XMLHttpRequest? XMLHttpRequest is an API provided by most browsers which allows client-scripting language such as Javascript to use for making requests to a server. It handles both the request to a server and response from the server. We use Javascript to create XMLHttpRequest objects. Summary: - XMLHttpRequest is an API provided by most browsers - Handles both request/response from the server - Javascript is used to create XMLHttpRequest objects A request from an XMLHttpRequest object can be sent to a URL via a GET or POST method ( click here for in depth GET or POST methods ) . The requests can also be set to an asynchronous or synchronous connection. An asynchronous connection means that , while waiting for the response from the particular server, the page in the particular Javascript segment can multitask. EG, writing a new email on the gmail interface. The response from the server can be fetched from the XMLHttpRequest object upon receipt of the response message, response can either be fetched as TEXT or XML. The text response can contain unstructured plain text or structured HTML text ( which means you can create your own RSS Feeds, now thats another tutorial for another time ) Summary: - XMLHttpRequest can be sent to a URL via GET or POST - Request can be set to asynchronous or synchronous connection ( one way/ two way ) - Response from server can be fetched from the XMLHttpRequest object - Can either be fetched as TEXT or XML Illustration: We can get the response status sent from the server by using several events associated with an XMLHttpRequest object: readState status onreadystatechange The readyState event provides the states (i.e. progress) of the HTTP request made by an XMLHttpRequest object. When sending an HTTP request message to the server, the states of the message can change from 0 to 4. The states are: 0: Request not initialised 1: Server connection established 2: Request received by server 3: Request being processed by server 4: Request is finished and response is ready The status of response messages from the server can be checked using the status event. The status of the response can be: 200: Request was completed and response given. 204: Request received but no response. 404: File/Resource not found. 400: Bad Request with the URL. 401: Not authorised to the file/resource. 403: Forbidden to access the file/resource. The onreadystatechange event is used to bind a function that will be called automatically when the readyState of an AJAX connection changes from 0.The function binded to the onreadystatechange event is usually responsible in deciding what to do with the progress of the connection and how to handle the response. Sorry it's abit wordy. But I promise the next post will be more practical! Next : Implementing AJAX in a web system

" When you teach, you understand " - My dad I am a 3rd year Computer Science student ( One more year till I get my degree ). I am going away from home for 5 months, Project-related. I decided to start this to fill in my free-time abroad. I am also doing this so I don't forget about everything that I've learned. This, I feel is useful . Feel free to correct me if you spot any errors. What is AJAX? You know how any requests you make on any web pages requires a full page reload? and then you have the same contents with just small extra information added. AJAX (Asynchronous Javascript and XML) is a technique of making requests to the server asynchronously (i.e. behind the scene without affecting other functioning parts of a system) AJAX makes use of old existing technologies (i.e. Javascript, XMLHTTPRequest object, HTML and CSS) . The idea of loading data asynchronously have been around since HTML 1, but the technique used an outdated concept of using a frame or iframe HTML element. Unlike standard requests to server, AJAX allows a single web page to make concurrent requests at any time. This allows a more responsive and dynamic web system. What do we have so far from the text above? - Requests are usually for the content that is needed by a user. - Response are then displayed on specific part of a web system without affecting the other existing content. - Unlike standard requests to server, AJAX allows a single web page to make concurrent requests at any time. The idea of loading data asynchronously have been around since HTML 1, but the technique used an outdated concept of using a frame or iframe HTML element ( I have never done this before but for those did, can please share? ) An illustration: Technologies involved in an AJAX-driven web systems: XMLHttpRequest: To make requests to server Javascript: To handle responses from server Server-Scripts: To handle requests from client HTML: To structure the result CSS: To style the result Here's an overview: Next : AJAX Tutorial Part 2: XMLHttpRequest Response

I've been working on a text editor for canvas that works via javascript. Does anyone know how to translate the mouse cursor to the next line with the enter key? Also is it possible to have it place images in it as well and display a text cursor? This my function for the keys so far: function addletter(letter) { // Gets letter input and adds it to the position of the cursor keyHistory += letter; ctx.clearRect(0, 0, 300, 300); ctx.fillText(keyHistory, 20, 20); } function keyUpHandler(event) { // Gets the user input and adds it as the parameter for the addletter function var letters = "abcdefghijklmnopqrstuvwxyz"; var key = event.keyCode; if (key > 64 && key < 91) { var letter = letters.substring(key - 64, key - 65); addletter(letter); } if (key == 13){ // keycode for enter } } My canvas is 800 wide by 1200 in height.

Good day, I am experimenting with Firebase and its workings, but now there is some weird stuff occurring. I don't think it has anything to do with Firebase itself. The problem is that somehow the exists variable stays false. When I set it to true in the playerExists function it somehow gets back to false when it is checked. This script basically needs to check if the player already exists, this is the datastructure in Firebase: { "players" : { "Maeb" : { "name" : "Maeb" } }} See this picture for the web console output (don't worry about the first line of the console, this happens when I refresh the page, it does not affect the connection with firebase, afaik) (edit: sorry for the spelling mistake, 'chose' should be 'choose') : It returns false when it should return true, as you can see playerExists executed because it inserted text to let the user know that name is taken. Here is the full code : /* * * File : script.js * Author : maeb * (c) 2014 * */(function() { var players = new Firebase("https://cc-charactersheet.firebaseio.com/players/"); var player; var exists = false; document.getElementById('create').addEventListener('click', function() { var player_name = document.getElementById('player_name').value; if (doesPlayerExist(player_name)) console.log(true); else console.log(false); }); function doesPlayerExist(player_name) { players.once("value", function(snapshot) { var data = snapshot.val(); for (var key in data) { if (key == player_name) playerExists(); } }, function(error) { console.log("Error: " + error); }); return exists; } function playerExists() { var pli = document.getElementById('player-login-info'); if (pli) pli.parentElement.removeChild(pli); exists = true; var exists_message = document.createElement('p'); exists_message.className = 'four columns offset-by-two red centered'; exists_message.id = 'player-login-info'; exists_message.textContent = 'That player already exists, please choose another name'; document.getElementById('login-form').insertBefore(exists_message, document.getElementById('login')); }})(); So yeah, that is a quite interesting problem. I hope you can help me out!

Hi, does anyone know how to get user input from a keylistener and input numbers on a canvas? Is there a method of implementing a text cursor to signal where the text is going to be input and enter keys? Also can you set text boundaries? Here is my current code for letter input: window.addEventListener("keyup", keyUpHandler, true); function addletter(letter) { keyHistory += letter; ctx.clearRect(0, 0, 300, 300); ctx.fillText(keyHistory, 20, 20); } function keyUpHandler(event) { var letters = "abcdefghijklmnopqrstuvwxyz"; var key = event.keyCode; if (key > 64 && key < 91) { var letter = letters.substring(key - 64, key - 65); addletter(letter); } }

Hello, i hope you all are doing well, I'm developing wordpress plugin that will allow people to create google hangouts group and that group will display on a website, whenever someone wenst to my website he will see all google hangouts groups and how much people are in those groups talking ( i know max is 10 ). He will be able to create his own group and if he will do that his group also will display in website OR he will be able to join existing groups and talk with people. My questions: 1. How can i use google hangouts API in php/javascripts ( more examples better ) 2. How can i get people that are in hangouts group and display with php/javascript in my website their photos if they does not have photos it will show default picture that i will select with code. 3. How can i display groups on website with php/javascript whenever group is created by user? More examples more better for these questions, main problem that i dont know how to insert and use tgoogle hangouts api and i find difficult to regonize if documentation that i'm reading is for website or for mobile app for example: https://developers.google.com/+/hangouts/api/gapi.hangout here i found class Participant( which how i understand allows to get people information from the hangout group and display it somewhere, but the problem is i dont understand wether this is for website or for something else, if i would know answers or see examples to my questions it would be much easier to develop what im trying to do, because i was searching for hours really did and didn't find anything understandable and i'm not noob on php just i find this especially hard. Kind Regards, Evelina

Hi everyone, I'm just wondering if there is a way to choose where to save a file in a web application. I know it is very unsecure, and I also know that the browser is the one who chooses where to save a file when downloading. But I am not making a consumer/public website, I'm currently making a private system so I need a way on how to force a web application to show the "Save as" dialog and enable the user to choose where they want to save the file. Thank you all in advance....

I am fiddling with Javascript classes and objects. Now I would like to add an eventListener to every Box object. It does not want to work though. However, when I remove the for-loop and put 0 in a variable and use that, it works. When I take a look at the console it says: 'TypeError: boxes[j] is undefined'. My question is: "Why doesn't this work and how can I get this to work?" Here is my full code : <!DOCTYPE html><html><head> <meta charset="utf-8"> <title>JS OO</title> <style type="text/css"> #container { width: 50%; height: 100%; margin-left: 25%; } .box { width: 100px; height: 100px; margin-left: auto; margin-right: auto; margin-bottom: 20px; background-color: #6cf; } </style></head><body> <div id="container"> <div class="box 0"></div> <div class="box 1"></div> <div class="box 2"></div> <div class="box 3"></div> <div class="box 4"></div> </div> <script type="text/javascript"> var boxes = []; document.body.onload = function() { for (var i = 0; i < 5; i++) { var boxDiv = document.getElementsByClassName(i)[0]; boxes[i] = new Box(boxDiv); } for (var j = 0; j < 5; j++) { boxes[j].div.addEventListener('click', function() { boxes[j].setBackgroundColor(); }, false); } } function Box(div) { this.div = div; console.log(this.div + ' was created'); } Box.prototype.setBackgroundColor = function() { this.div.style.backgroundColor = '#ddd'; console.log('changed background color of ' + this.div); } </script></body></html> This works as it should : var j = 0;boxes[j].div.addEventListener('click', function() { boxes[j].setBackgroundColor(); }, false); Thank you.

I am starting a new part time job soon and they use Alpha Five and ColdFusion (not using that again) to build/manage their webpages. They code from scratch so no frameworks are used. Anyone out there who code in Alpha Five? I need tips, examples and any sample code that you might want to share. Also if it is possible to message you whenever i need help in something. Thanks lots!

Here's the code http://jsfiddle.net/x5xH5/2/ Some unknown reason the line of the width doesn't change after Math.Random hits it's highest value. You have to move the mouse over the line to understand what i'm saying here.

So I've basically done what I can think of in terms of fixing up these websites but I feel like there is room for improvement. I've been adding random cliche things but I'm kinda at a loss for what to do now This site is basically me reverse engineering and cobbling together a bunch of code I've come across I've the same base for all these but I'll fork them off based on what each need http://seireiju.net/ personal site, anime, manga, etc I'm trying to use this for a colorscheme http://colorschemedesigner.com/#4s51TuOsPw0w0 would also like suggestions for wordpress themes that would match well with this page (I would use squarespace but I don't feel like paying for that right now) Newest code changes will be found here http://skandharaj.com/ personal site, tech, daily life, etc I'm trying to use this for a colorscheme http://colorschemedesigner.com/#4s51TuOsPw0w0 would also like suggestions for wordpress themes that would match well with this page http://test.technotundra.com/ originally our "Forums are down" site, which I decided to eventually make into our main page, kinda want to have the main page to be where we can have all the important info readily accessible for people I'm trying to use this for a colorscheme http://colorschemedesigner.com/#3A21T----w0w0 I will replace those memes with images related to our content once I have the rest of this stuff ready

Hi, I would just like to present to you my most recent project that i have been working on and have just published for public download. YouTweak is an application that aims to improve upon your YouTube experience. It adds many useful features, tweaks and additions to the site which i hope will meet your approval. Feature List Remove Subscription Videos Remove Watched Videos Subscription links are made HD Youtube Subscriptions as Default Page Stop autoplay of videos Remove all subscription videos Load all subscription videos If you like the application please feel free to leave a review on the site. Thanks Download Link https://chrome.google.com/webstore/detail/youtweak-for-youtube/cfgpigllcihcpkbokdnmpkjobnebflgh

Hey guys, Some background: I do a lot of Java and C/C++ development and do it with the Eclipse IDE. I just got a job doing a bit of backend JavaScript development. Now I'm okay with doing PHP and JavaScript coding and testing using a browser and simple text editor (I use Sublime Text for basic editing) but given that the backend system is much larger than a few files, I suspect this solution may not be viable. I'm hoping someone here may be able to provide a better solution or convince me that the way I'm proceeding is perfectly fine. Bonus points if the solution works on OS X. Also, I may have to look forward to doing .net/C# development. I'm currently working on a Mac, thereby making development difficult. I was wondering if there was a solution for getting this up and running on my machine. I gave Emonic on Eclipse a shot but it was last updated in 2010, didn't install, and probably isn't supported anymore. I could just as easily purchase a Windows laptop for development but that's quite a chunk of change that I'm going to do my best to avoid spending. One last note: booting into Windows on a Macbook Pro is a terrible experience and is one that I can't recommend. Just in case someone may have suggested this solution. Thanks a lot!

Hello I began learning how to make a website a while ago. I completed codeacademy.com all the way through python about 2 months ago (including html, css, jquery, and javascript). However, when I look back on these lessons, I remember very little. I also found that codeacademy and other tutorials seemed incomplete and only went over the basics. So, I would like something, preferably a book, that can teach me how to make a complete website. I would like the book to include html5, css, php, and jquery. I would like it to start off at the basics, but still be able to teach me more advanced features of web development. Thanks for the help

Hello LinusTechTips community! I am in need of some help and maybe some resources for a Live chat system I plan on developing for my panel. The chat would need the following: Auto refreshing Fast Non-Resource intensive It would only have to between 3 people the Myself(just to observe), the Employee & the Client Functions Main Chat page w/ 5 second refreshing Send Button Any thing else that might be needed I already have the login & registar system in place. Thanks for any help you may able to provide! EDIT: We use Unique ID's for each project 1 Chat per project All logged. P.S. Im not the greastest at PHP.

Can anyone help me? So I have a normal table with inputs inside td's. Now what I want to do is when the tr:last-child>td:first-child>input has something in it, a new row automatically be added. And then when you erase the value of tr:nth-last-child(2)>td:first-child>input, the tr:last-child should be deleted. Somehow the function work except to the dynamically added markups.... http://jsfiddle.net/7XZEV/

A Small Introduction to mincss Note: I'm a not experienced with Python. I have some general knowledge about it and some scripting experience with other languages as well as some programming knowledge in C/C++, but Python is mostly uncharted territory for me. So if anyone spots some serious flaw or something that could be done alot better, feel free to point it out (politely ) and I will happily correct it. I'm mainly doing this because I have found the info on mincss which is out there not very beginner friendly. That also means that I may not always describe the most clever way of doing things for the sake of preserving understandability. Having said that: What Is It? A tool which strips your CSS files of unneeded stuff. You give it a URL, it will download that and parse it. Be careful though: If you have a CSS file used for several pages on your site, it will mark stuff that is not used on the URL you've given as unneeded. Completely logical of course, but important to keep in mind. What Do I Need Python2 (not Python3, as of 2013-OCT-08) mincss, obviously lxml (a Python extension) cssselect (also a Python extension) PhantomJS is optional I'm trusting you can manage to install this stuff yourself, if you're on a Linuxmachine it should be in the repositories (it is for Arch as of 2013-OCT-08). Let's Get Started Note: I'm doing this on a Linux machine, if you discover something I'm describing here not working on a Win PC, please let me know. Start a command terminal and change into the directory where you have stored mincss' files. Then start a Python2 console. On my Linux machine I simply type python2 into the console and hit return. If it's worked you should be greeted with a screen that has three > at its left: >>>Then, type in the following: >>> from mincss.processor import Processor>>> p = Processor()This will basically load mincss into the console (yes, I know: a simplification)and initialize an object named p of type Processor. After that, you give it an URL to download and instruct it to process whatever it has found there. >>> p.process_url('http://www.yourdomain.com/')>>> p.process()This will detect any inline CSS if I understand things correctly, I have not yettried this out myself. >>> p.inlines[]And this searches the document for linked CSS stylesheets and puts the resultsinto an array, starting at index 0 (so, the first stylesheet will be located at links[0], the second one at links[1] etc.). Don't mind the funky output. >>> p.links[<mincss.processor.LinkResult object at 0x10a3bbe50>, <mincss.processor.LinkResult object at 0x10a4d4e90>]Now you grab the first stylesheet and initialize it into object one(again, the name is arbitrary). If more than one stylesheet has been found, iterate through the array links[k] until you've initialized each stylesheet into an object (alternatively, you can of course grab one stylesheet, proceed further, then come back and initialize the second stylesheet into the same object etc.). >>> one = p.links[0]You can check which CSS sheet has been grabbed by entering this command, it willgive back the name and location of said stylesheet. >>> one.href'//d1ac1bzf3lrf3c.cloudfront.net/static/CACHE/css/c98c3dfc8525.css'Now for the interesting bit: This will give out the length of the stylesheetbefore it has been processed... >>> len(one.before)83108...and after processing: >>> len(one.after)10062By entering the following commands, you can print out the entire stylesheetsonto the screen if you wish: >>> one.after>>> one.beforeNow, this is nice and all, but what we would really like is generate a new, slimmed downstylesheet, wouldn't we? Thought so. Alright then, first we open a new filehandle for writing: (It is entirely possible mincss has some sort of integrated function/method for creating new, stripped down, files, but I have not been able to find anything on that so until informed otherwise I will presume it does not.) >>>filehandle=open('yournewfilename.css','w')>>>filehandle.write(one.after)>>>filehandle.close()And voilà, you should now have a new file of the name yournewfilename.css in your current directory.What Next? As said I'm no Python guru, and I only encountered mincss for the first time a day or so ago, so there's certainly some stuff missing from here, but it gets the job done which I think is probably at the top of many people's list. I've also read that it can do Javascript, but have not played around with that yet. If you wanted to automate this process, you could also write a script taking advantage of mincss, for an example see mincss' own examples here. Sources Official Site mincss Github Stackoverflow If you have any corrections, amendments, suggestions etc. feel free to post. Happy coding, -aw

So here is the code so far. I keep getting a syntax error. also sometimes I'll change one thing and it will say numHours is not defined and codecademy says I passed. If you tell me what's wrong please EXPLAIN WHY!!!! I still want to learn! Thanks in advance!

Hi there, I am using Notepad ++ for my HTML and CSS but really want to get into JavaScript and ASP. I was wondering if there is a text editor which is kinda preferred when writing in JS/ASP (or a better one in general).

So I am trying to switch colors with a delay of 500ms until the user lets it stop. Here is a jsfiddle page : http://jsfiddle.net/jxrf34ww/ Here is the code : <button onclick="animate()" id="start">start</button><button onclick="stop()" id="stop">stop</button><div id="square"></div> css is not important var intervId;function animate() { intervId = setInterval(changeColor, 500);}function stop() { clearInterval(intervId);}function changeColor() { var square = document.getElementById("square"); if (square.style.background == "#3498db") square.style.background = "#2ecc71"; else square.style.background = "#3498db";} I was creating this after looking at a MDN article about setInterval, here is the section I am refering to : https://developer.mozilla.org/en-US/docs/Web/API/window.setInterval#Example_2.3A_Alternating_two_colors It is probably some stupid mistake that is causing the square not to switch colors, but thank you for helping me.

<div> <h1 style="text-align: center;">Hello World from HTML. </h1> <div id="script"> <script type="text/javascript"> function myFunction() { document.getElementById("innerScript").innerHTML = "<h1>Hello World from JavaScript.</h1>"; } </script> </div> <div id="innerScript" style="color: blue; -webkit-text-shadow: 2px 2px 20px; text-shadow: 2px 2px 20px; text-align: center;" /> <br /> <br /> <div style="text-align: left;"> <input id="Button1" type="button" value="Surprise Me" onclick="myFunction()" /> <br /> <br /> </div> </div>

So essentially i would like to know if you can make a code in wich the webbrowser shuts down your pc. The reasoning behind this is that my teacher kind of challenged me to find this, and im asking the forums because of the knowledge the people here have. Thank you

I'm a noob a Javascript and have ran into a slight issue! The issue starts from the two lines starting with "g2." The error reads on line 107 Multiple markers at this line - Syntax error on token "(", delete this token - Syntax error on tokens, VariableDeclarator expected instead The error reads on line 108: Multiple markers at this line - Syntax error on tokens, VariableDeclarator expected instead - Syntax error on token "(", delete this token If someone could inbox me too as I need help with other coding! private void update() {} private void draw() {} private void drawToScreen() {} Graphics g2 = getGraphics(); g2.drawImage(image, 0, 0, null); g2.dispose(image, 0, 0, null); public void keyTyped(KeyEvent key) {} public void keyPressed(KeyEvent key) {} public void keyReleased(KeyEvent key) {}

I am retrieving a string from the YouTube API (the video description) and shortening it in my PHP code to 170 characters. However, when it displays, it's normally fine, but if it contains a URL, it will wrap and leave a lot of whitespace because I'm trying to display it in a narrow box, which results in some content overflowing. Is it possible to use javascript or JQuery to truncate the string on the client side so that it fits in the box and still ends in an ellipsis if truncated? I can upload a screenshot if that would help.