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jQuery.each( object, callback )
A generic iterator function, which can be used to seamlessly iterate over both objects and arrays. Arrays and array-like objects with a length property (such as a function's arguments object) are iterated by numeric index, from 0 to length-1. Other objects are iterated via their named properties.
This function is not the same as
$().each() - which is used to iterate, exclusively, over a jQuery object. This function can be used to iterate over anything.
The callback has two arguments:the key (objects) or index (arrays) as the first, and the value as the second.
If you wish to break the each() loop at a particular iteration you can do so by making your function return false. Returning non-false is the same as a
continue statement in a for loop, it will skip immediately to the next iteration.
Arguments:| object | Object | |
|---|
| The object or array to iterate over. |
| callback | Function | |
|---|
The function that will be executed on every object.
function callback(indexInArray, valueOfElement) {
var booleanKeepGoing;
this; // == valueOfElement (casted to Object)
return booleanKeepGoing; // optional, unless false
// and want to stop looping
}
|
Examples:| Name | Type |
|---|
Iterates through the array displaying each number as both a word and numeral
var arr = [ "one", "two", "three", "four", "five" ];
var obj = { one:1, two:2, three:3, four:4, five:5 };
jQuery.each(arr, function() {
$("#" + this).text("My id is " + this + ".");
return (this != "four"); // will stop running to skip "five"
});
jQuery.each(obj, function(i, val) {
$("#" + i).append(document.createTextNode(" - " + val));
});
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<script src="http://code.jquery.com/jquery-latest.js"></script>
<script>
$(document).ready(function(){
var arr = [ "one", "two", "three", "four", "five" ];
var obj = { one:1, two:2, three:3, four:4, five:5 };
jQuery.each(arr, function() {
$("#" + this).text("My id is " + this + ".");
return (this != "four"); // will stop running to skip "five"
});
jQuery.each(obj, function(i, val) {
$("#" + i).append(document.createTextNode(" - " + val));
});
});
</script>
<style>
div { color:blue; }
div#five { color:red; }
</style>
</head>
<body>
<div id="one"></div>
<div id="two"></div>
<div id="three"></div>
<div id="four"></div>
<div id="five"></div>
</body>
</html>
Iterates over items in an array, accessing both the current item and its index.
$.each( [0,1,2], function(i, n){
alert( "Item #" + i + ": " + n );
});
Iterates over the properties in an object, accessing both the current item and its key.
$.each( { name: "John", lang: "JS" }, function(i, n){
alert( "Name: " + i + ", Value: " + n );
});
