Check if a key exists in an object

JavaScript performance comparison

Revision 2 of this test case created

Preparation code

 
<script>
Benchmark.prototype.setup = function() {
    var obj = { a: true, b: true, c: true, d: true, e: true, f: true };
};
</script>

Test runner

Warning! For accurate results, please disable Firebug before running the tests. (Why?)

Java applet disabled.

Testing in unknown unknown
Test Ops/sec
in operator
if ("b" in obj) {

}
pending…
array notation
if(obj["b"] !== undefined) {

}
pending…
array notation 2 (obj["b"])
if(obj["b"]) {

}
pending…

Compare results of other browsers

Revisions

You can edit these tests or add even more tests to this page by appending /edit to the URL. Here’s a list of current revisions for this page:

0 comments

Add a comment