javascript - Which is faster, For Loop or .hasOwnProperty? -

i working on project needed pull list of excluded users out of giant list of user data. made me wonder if faster use double for loop excluded id's in array. or if putting id's in object properties , using .hasownproperty() faster.

var mainlist = large json object of data. var earray = ["123456","234567","345678","456789","012345"]; var eobject = {"123456":"0","234567":"0","345678":"0","456789":"0","012345":"0"}; 

using double for loop approach:

for(i=0; < mainlist.length; i++){     for(j=0; j < earray.length; j++){         if(mainlist[i]['id'] === earray[j]){            //do         }     } } 

using .hasownproperty() approach:

for(i=0; < mainlist.length; i++){     if(eobject.hasownproperty(mainlist[i]['id'])){        //do     } } 

i realize there other ways make loops faster, storing lengths in variables. i've tried simplify this.

thanks information.

if think it, make sense .hasownproperty() approach faster because uses 1 for loop.

wrong

i little surprised. expecting double loop slower. guess can't under estimate speed of for loop.

double loop

while me seem slowest, ended being fastest benching @ 7,291,083 ops/sec

.hasownproperty()

i can see how slower because functions slower statements. benches @ 1,730,588 ops/sec

if..in

@geuis answer included if..in statement , thought test speed of seem fastest benching @ 2,715,091 ops/sec still doesn't beat loops.

conclusion

for loops fast. double loops runs more 4 times faster using .hasownproperty() , 3 times faster using if..in condition. however, performance not noticeable; speed important have need complicate things. in opinion if..in method way go.

test yourself in browser. using google chrome 28.