This is the function I wrote to retrieve all the values in an given object.
function getValues(data){
var keys = Object.keys(data);
var values = [];
for(var i = 0, l = keys.length, key; i< l; i++){
key = keys[i];
values.push(data[key]);
}
return values;
}
Is there any builtin way to retrieve all the values in an object? Something like this exists in java for HashMaps. I know JS has a method for retrieving all the keys by doing Object.keys(obj).
Probably the most concise way of getting an array of the values contained within an object is to use Object.keys and Array.prototype.map:
obj = {
a: 1,
b: 2,
c: 3
};
values = Object.keys(obj).map(function (key) {
return obj[key];
});
Otherwise there's no standardized way of getting an array of an object's values.
For iterating, ES6 introduces a for..of loop which will iterate through an object's values:
for (value of obj) {
console.log(value); //1, 2, 3
}
ES7 is slated to introduce array comprehensions, so generating the values array could be written as:
continued from above:values = [for (x of Object.keys(obj)) obj[x]];
If you're already using underscore, you can use the _.values method:
_.values(obj); //[1, 2, 3]
If you just want an efficient implementation for this utility function, the lodash source is:
lodash.js v2.4.1 lines 2891-2914/**
* Creates an array composed of the own enumerable property values of `object`.
*
* @static
* @memberOf _
* @category Objects
* @param {Object} object The object to inspect.
* @returns {Array} Returns an array of property values.
* @example
*
* _.values({ 'one': 1, 'two': 2, 'three': 3 });
* // => [1, 2, 3] (property order is not guaranteed across environments)
*/
function values(object) {
var index = -1,
props = keys(object),
length = props.length,
result = Array(length);
while (++index < length) {
result[index] = object[props[index]];
}
return result;
}
[for (x of obj) x]?
You could do this, in newer Browsers:
Object.defineProperty(Object.prototype, 'values', {
get:function(){
return function(o){
var a = [];
for(var i in o){
a.push(o[i]);
}
return a;
}
}
});
var arrayOfValues = Object.values({a:'A',b:'B',c:'C'});
Really, I would just do:
function objectValues(obj, inherited){
var a = [];
for(var i in obj){
var v = obj[i];
if(inherited){
a.push(v);
}
else if(obj.hasOwnProperty(i)){
a.push(v);
}
}
return a;
}
var notInheritedArrayOfValues = objectValues({a:'A',b:'B',c:'C'});
var inheritedArrayOfValues = objectValues({a:'A',b:'B',c:'C'}, true);
for..inseems more suitable for objects.valuesfunction.