Run results for: FormData conversion: Object.fromEntries vs for loop

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/139.0.0.0 Safari/537.36

Browser: Chrome 139

Operating system: Windows

Device Platform: Desktop

Date tested: 10 months ago

for of loop

457K/s

for of loop + array support

400K/s

Object.fromEntries

393K/s

forEach

306K/s

View exact numbers

Test name	Executions per second
✓ for of loop	456,588 Ops/sec
for of loop + array support	400,368 Ops/sec
Object.fromEntries	393,403 Ops/sec
forEach	306,471 Ops/sec

HTML Preparation code:

<!--your preparation HTML code goes here-->

Script Preparation code:

/*your preparation JavaScript code goes here
To execute async code during the script preparation, wrap it as function globalMeasureThatScriptPrepareFunction, example:*/
async function globalMeasureThatScriptPrepareFunction() {
    // This function is optional, feel free to remove it.
    // await someThing();
}

Tests:

Object.fromEntries
const formData = new FormData(); formData.append("x", "1"); formData.append("x", "2"); formData.append("x", "3"); formData.append("x", "4"); formData.append("y", "1"); formData.append("z", "1"); const object = Object.fromEntries(formData);
for of loop
const formData = new FormData(); formData.append("x", "1"); formData.append("x", "2"); formData.append("x", "3"); formData.append("x", "4"); formData.append("y", "1"); formData.append("z", "1"); const object = {}; for(const entry of formData){ object[entry[0]] = entry[1]; }
forEach
const formData = new FormData(); formData.append("x", "1"); formData.append("x", "2"); formData.append("x", "3"); formData.append("x", "4"); formData.append("y", "1"); formData.append("z", "1"); const object = {}; formData.forEach((value, key) => object[key] = value);
for of loop + array support
const formData = new FormData(); formData.append("x", "1"); formData.append("x", "2"); formData.append("x", "3"); formData.append("x", "4"); formData.append("y", "1"); formData.append("z", "1"); const object = {}; for(const [key, value] of formData){ if(typeof object[key] !== "undefined"){ if(Array.isArray(object[key])){ object[key].push(value) } else { object[key] = [object[key], value] } } else { object[key] = value; } }