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Subject classification: this is a design resource. |
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Subject classification: this is a technology resource. |
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Subject classification: this is an information technology resource. |
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Subject classification: this is an engineering resource. |
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Educational level: this is a tertiary (university) resource. |
Statements
The following statements allow the coder to specifically direct the process in alternative packages.
DOM editing
Also see: Web_Design/Getting_to_know_the_Document_Object_Model_with_JavaScript
Attributes selection
Finding names, identification, values, colors, and other settings is possible via JavaScript.
var drawnName = document.getElementsByTagName('div'); //get the div collection
var process = drawnName.length;
for (var i = 0; i < process; i++) { //process through the div collection
var nos = i;
var myattrib = 'onclick'; //give each one my mouse click function
var newVal = "myotherFunction(" + nos + ")";
var post = drawnName[i];
post.setAttribute(myattrib, newVal); //set it altogether
};
Element selection
See also: Web_Design/JavaScript_Challenges
The code to seek an element via a collection of those elements present:
var script = document.getElementsByTagName('script'); //find the script collection
var thus = script[0].parentNode; //pick the parent
thus.removeChild(script[0]); //remove the first script in the collection
The code to add an element could be this (appending the body (HTML) element):
function develop() {
var script = document.createElement("script"); //create a spare element
script.type = "text/javascript";
script.src = "index.js";
document.body.appendChild(script); //paste it to the body
}
Note: this will not work in an XML document. XML documents don't have the HTML Body tag/element.
Activity: Make a Simple CAD
JavaScript for XML
Resources: http://en.wikipedia.org/wiki/ECMAScript_for_XML
XMLHttpRequest
AJAX
See also: Web_Design/AJAX_Challenges
XSLT
Client-side and user scripts
Client-side
Userscripts
Resources: http://userscripts.org/
See http://en.wikipedia.org/wiki/Greasemonkey
Server-side scripts
REST servers and javavascript in http
Resources: http://rest.elkstein.org/2008/02/using-rest-in-javascript.html
See : Web_programming,_an_example
Javascript Games and event tools
Timers
JavaScript establishes two time oriented objects.
- setTimeout
setTimeout(alert('I waited this time'), 1000);
- setInterval
Events
The following gives an example of catching a key event to describe it's code (via a label). It's extremely simple and may only work in FireFox or something similar. Better snippets can easily be found to suit numerous purposes. Try this example if you're unsure what Unicode numbers follow your keyboard strokes.
<!DOCTYPE html>
<html>
<head><title>Lesson keys</title></head>
<body>
<script>
function tohear(e) {
var textTo = document.getElementById('textbox');
var keycode = e.charCode;
textTo.innerHTML += " " + keycode + "<br>";
};
window.onkeypress = tohear;
</script>
Character codes for keys <br>
<label id="textbox"></label><br>
</body>
</html>
A good detector is found below this page/link Detecting keystrokes. If you notice, it will operate differently in Firefox, Chrome, or IE, (for mathematical operators mostly).
Maps, Drawing, Design
Maps
Resources: https://developers.google.com/maps/documentation/javascript/tutorial
See http://www.wikihow.com/Geocode-an-Address-in-Google-Maps-Javascript
Drawing
SVG
Resources: http://www.carto.net/svg/manipulating_svg_with_dom_ecmascript/ or
http://srufaculty.sru.edu/david.dailey/svg/SVG_serialize.html
Browser identification
Excluding IE
Internet Explorer will recognize a simple inclusion from within HTML comments:
<!--[if IE]>
<p>This is the line where only IE will overlook that it's a comment.
It's a good place to source the dot-js file for IE browsers</p>
<![endif]-->
Some logic is allowed through the use of gt for greater than (or lt for lower than):
<!--[if gt IE 6]>
<br>
This is a comment overlook for IE browsers that are greater than IE6<br>
<![endif]-->
<!--[if !IE]> <-->
<p> This is a line between two comments creating an IE exclusion.</p>
<!--> <![endif]-->
This merely an HTML solution to include scripts that specifically apply within IE (or the opposite).
Browser specific code/script and javascript
Mozilla
Resources: JavaScript Guide
Error handling
Resources: msdn.microsoft error handling examples
Alternative ECMAscript languages
ECMAscript
ActionScript
ActionScript is the scripting language in use in Flash website/movie development.
ActionScript isn't very different from JavaScript. It applies the same language style to a timeline application. And it offers several commands to work with movies. But, it essentially adopts the same ECMAscript requirements for it's language.
Developing with JavaScript
JavaScript is a standardized language best described by popular use. Alterations to the language need to be adopted. Deprecation of former code-practice is common in the standardization process. The community of developers is social. This means that they migrate to new instances of JavaScript usage. Information overload is expected for individuals attempting the intensive learning curve. New standards are adopted progressively so that programmers can migrate their assets. Most coders will attempt some restriction of their required skill-set. It's best to communicate/share via a project when producing larger developments. See: https://developer.mozilla.org/en-US/docs/JavaScript
Developing with React
React is a Javascript library built and maintained by Facebook. It is used for developing of web and mobile apps. React relies on Virtual DOM for updating the UI which sometimes creates performance issues.