# jQuery.each()

Categories: Utilities

## jQuery.each( collection, callback(indexInArray, valueOfElement) ) Returns: Object

Description: 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.

- #### version added: 1.0jQuery.each( collection, callback(indexInArray, valueOfElement) )

  collectionThe object or array to iterate over.

  callback(indexInArray, valueOfElement)The function that will be executed on every object.

The `$.each()` function is not the same as $(selector).each(), which is used to iterate, exclusively, over a jQuery object. The `$.each()` function can be used to iterate over any collection, whether it is a map (JavaScript object) or an array. In the case of an array, the callback is passed an array index and a corresponding array value each time. (The value can also be accessed through the `this` keyword, but Javascript will always wrap the `this` value as an `Object` even if it is a simple string or number value.) The method returns its first argument, the object that was iterated.

    $.each([52, 97], function(index, value) {
      alert(index + ': ' + value);
    });

This produces two messages:

0: 52
1: 97

If a map is used as the collection, the callback is passed a key-value pair each time:

    var map = {
      'flammable': 'inflammable',
      'duh': 'no duh'
    };
    $.each(map, function(key, value) {
      alert(key + ': ' + value);
    });

Once again, this produces two messages:

flammable: inflammable
duh: no duh

We can break the `$.each()` loop at a particular iteration by making the callback 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.

### Examples:

#### Example: Iterates through the array displaying each number as both a word and numeral

    <!DOCTYPE html>
    <html>
    <head>
      <style>
      div { color:blue; }
      div#five { color:red; }
      </style>
      <script src="http://code.jquery.com/jquery-1.7rc2.js"></script>
    </head>
    <body>

      <div id="one"></div>
      <div id="two"></div>
      <div id="three"></div>
      <div id="four"></div>
      <div id="five"></div>
    <script>
        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("Mine is " + this + ".");
           return (this != "three"); // will stop running after "three"
       });

        jQuery.each(obj, function(i, val) {
          $("#" + i).append(document.createTextNode(" - " + val));
        });
    </script>

    </body>
    </html>

#### Demo:

#### Example: Iterates over items in an array, accessing both the current item and its index.

    $.each( ['a','b','c'], function(i, l){
       alert( "Index #" + i + ": " + l );
     });

#### Example: Iterates over the properties in an object, accessing both the current item and its key.

    $.each( { name: "John", lang: "JS" }, function(k, v){
       alert( "Key: " + k + ", Value: " + v );
     });