loops - How to iterate over a JavaScript object? -

i have object in javascript:

{     abc: '...',     bca: '...',     zzz: '...',     xxx: '...',     ccc: '...',     // ... } 

i want use for loop properties. , want iterate in parts (not object properties @ once).

with simple array can standard for loop:

for (i = 0; < 100; i++) { ... } // first part (i = 100; < 300; i++) { ... } // second (i = 300; < arr.length; i++) { ... } // last 

but how objects?

for objects, use for .. in :

for (var key in yourobject) {   console.log(key, yourobject[key]); } 

to avoid logging inherited properties, check hasownproperty :

for (var key in yourobject) {    if (yourobject.hasownproperty(key)) {       console.log(key, yourobject[key]);    } } 

this mdn documentation explains more how deal objects , properties.

if want "in chunks", best extract keys in array. order isn't guaranteed, proper way. in modern browsers, can use

var keys = object.keys(yourobject); 

to more compatible, you'd better :

 var keys = [];  (var key in yourobject) {            if (yourobject.hasownproperty(key)) keys.push(key);  } 

then can iterate on properties index: yourobject[keys[i]] :

for (var i=300; i<keys.length && i<600; i++) {     console.log(keys[i], yourobject[keys[i]]); }