by Unknown in javascript , Tutorial 0
function htmlDecode(input){
var e = document.createElement('div');
e.innerHTML = input;
return e.childNodes.length === 0 ? "" : e.childNodes[0].nodeValue;
}htmlDecode("<img src='myimage.jpg'>");
// returns "<img src='myimage.jpg'>"
by Unknown in javascript , Tutorial 0
var myString = "abcdefg";
var newString = myString.substr(0, myString.length-4);
// newString is now "abc"var myString = "abcdefg";
var newString = myString.substr(2);
// newString is now "cdefg"The substr function can be called on any string with two integer parameters, the second optional. If only one provided, it starts at that integer and moves to the end of the string, chopping off the start. If two parameters provided, it starts at the first number and ends at the second, chopping off the start and end as it is able.
abcdefghijklmnopqrstuvwxyz
Press to Chop
by Unknown in javascript , Tutorial 0
<script type="text/javascript">
<!--
function toggle_visibility(id) {
var e = document.getElementById(id);
if(e.style.display == 'block')
e.style.display = 'none';
else
e.style.display = 'block';
}
//-->
</script><a href="#" >Click here to toggle visibility of element #foo</a>
<div id="foo">This is foo</div>by Unknown in javascript , Tutorial 0
User Agent testing sucks, but sometimes you need it for subtle things. In my case I was using it to adjust what I was showing for keyboard shortcut keys (Command or Control). Nothing super major.
if (navigator.userAgent.indexOf('Mac OS X') != -1) {
$("body").addClass("mac");
} else {
$("body").addClass("pc");
}The statements in there use jQuery to add a body class, but that's not required, you could do whatever.
by Unknown in javascript , Tutorial 0
Not all browsers support all attributes on all elements. There are a number of new attributes in HTML5, so the idea of testing to see what kind of browser environment you are in becomes every increasingly important.
function elementSupportsAttribute(element, attribute) {
var test = document.createElement(element);
if (attribute in test) {
return true;
} else {
return false;
}
};if (elementSupportsAttribute("textarea", "placeholder") {
} else {
// fallback
}by Unknown in javascript , Tutorial 0
HTML5 drag and drop is great for handling file uploads. But if that's the only thing you are using it for, it's nice to know if any particular dragenter or dragover event actually has files. Unlike, for example, just the dragging of some selected text.
Send the event object to this function and it will return the truth (assuming you are in a browser that supports all this):
function containsFiles(event) {
if (event.dataTransfer.types) {
for (var i = 0; i < event.dataTransfer.types.length; i++) {
if (event.dataTransfer.types[i] == "Files") {
return true;
}
}
}
return false;
}by Unknown in javascript , Tutorial 0
var isMSIE = /*@cc_on!@*/0;
if (isMSIE) {
// do IE-specific things
} else {
// do non IE-specific things
}