Sunday 29 December 2019

javascript - jQuery document.createElement equivalent?



I'm refactoring some old JavaScript code and there's a lot of DOM manipulation going on.




var d = document;
var odv = d.createElement("div");
odv.style.display = "none";
this.OuterDiv = odv;

var t = d.createElement("table");
t.cellSpacing = 0;
t.className = "text";
odv.appendChild(t);



I would like to know if there is a better way to do this using jQuery. I've been experimenting with:



var odv = $.create("div");
$.append(odv);
// And many more


But I'm not sure if this is any better.


Answer




here's your example in "one" line.



this.$OuterDiv = $('
')
.hide()
.append($('
')
.attr({ cellSpacing : 0 })
.addClass("text")
)
;






Update: I thought I'd update this post since it still gets quite a bit of traffic. In the comments below there's some discussion about $("

") vs $("
")
vs $(document.createElement('div')) as a way of creating new elements, and which is "best".



I put together a small benchmark, and here's roughly the results of repeating the above options 100,000 times:



jQuery 1.4, 1.5, 1.6



               Chrome 11  Firefox 4   IE9

440ms 640ms 460ms
420ms 650ms 480ms
createElement 100ms 180ms 300ms


jQuery 1.3



                Chrome 11
770ms
3800ms

createElement 100ms


jQuery 1.2



                Chrome 11
3500ms
3500ms
createElement 100ms



I think it's no big surprise, but document.createElement is the fastest method. Of course, before you go off and start refactoring your entire codebase, remember that the differences we're talking about here (in all but the archaic versions of jQuery) equate to about an extra 3 milliseconds per thousand elements.



Update 2



Updated for jQuery 1.7.2 and put the benchmark on JSBen.ch which is probably a bit more scientific than my primitive benchmarks, plus it can be crowdsourced now!



http://jsben.ch/#/ARUtz


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