Run results for: object key vs indexof

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/121.0.0.0 Safari/537.36

Browser: Chrome 121

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: 2 years ago

key lookup

20.1M/s

array indexed

10.4M/s

loop lookup

5.9M/s

View exact numbers

Test name	Executions per second
✓ key lookup	20,139,958 Ops/sec
array indexed	10,358,341 Ops/sec
loop lookup	5,894,736 Ops/sec

Script Preparation code:

var a = [{"id":7,"h":76},{"id":4,"h":34},{"id":9,"h":89}];
var b = [];
for(var i=0;i<a.length;i++)b[i] = a[i].id;
var c = [];
for(var i=0;i<a.length;i++)c[a[i].id] = a[i];

Tests:

loop lookup
for(var i in a)if(i.id==9)return i;
array indexed
return a[b.indexOf(9)];
key lookup
return c[9];