jQuery appending an array of elements

Question

You could use an empty jQuery object instead of an array:

var elements = $();
for(x = 0; x < 1000; x++) {
    elements = elements.add('<div>'+x+'</div>');
    // or 
    // var element = $('<div>'+x+'</div>');
    // elements = elements.add(element);
}
$('body').append(elements);

This might be useful if you want to do stuff with newly generated element inside the loop. But note that this will create a huge internal stack of elements (inside the jQuery object).

---

It seems though that your code works perfectly fine with jQuery 1.8.

You could just call

$('body').append(elements.join(''));

Or you can just create a large string in the first place.

var elements = '';
for(x = 0; x < 1000; x++) {
    elements = elements + '<div>'+x+'</div>';
}
$(document.body).append(elements);

Like you mentioned, probably the most "correct" way is the usage of a DocFrag. This could look like

var elements = document.createDocumentFragment(),
    newDiv;
for(x = 0; x < 1000; x++) {
    newDiv = document.createElement('div');
    newDiv.textContent = x;
    elements.append( newDiv );
}
$(document.body).append(elements);

^{.textContent is not supported by IE<9 and would need an conditional check to use .innerText or .text instead.}

Upgrade to jQuery 1.8, this works as intended:

​$('body')​.append([
    '<b>1</b>',
    '<i>2</i>'   
])​;​

Since $.fn.append takes a variable number of elements we can use apply to pass the array as arguments to it:

el.append.apply(el, myArray);

This works if you have an array of jQuery objects. According to the spec though you can append an array of elements if you have the DOM elements. If you have an array of html strings you can just .join('') them and append them all at once.

A slight change to your second approach:

var elements = [],
newDiv;
for (x = 0; x < 1000; x++) {
    newDiv = $('<div/>').text(x);
    elements.push(newDiv);
}
$('body').append(elements);

$.append() certainly can append an array: http://api.jquery.com/append/

.append(content) | content: One or more additional DOM elements, arrays of elements, HTML strings, or jQuery objects to insert at the end of each element in the set of matched elements.