I've got an object:
var obj = {
"Mike": 24,
"Peter": 23,
"Simon": 33,
"Tom": 12,
"Frank": 31
};
I want to create an array that holds the values of the object. The keys (key names) can be disregarded:
[24, 23, 33, 12, 31]
The order of the values is NOT important!
One solution (obviously) would be do have a function that takes the values and puts them into an array:
var arr = valuesToArray(obj);
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I will accept such a function as the answer. However, I would be more pleased if there would be an API function (ECMAScript, jQuery, browser-specific, ...) that could do this. Is there such a thing?
The obvious way would be to do a for-in loop, as @quixoto suggests, but just for the record, and since you are looking for a built-in way, you could pair the new ECMAScript 5 methods Object.keys
and Array.prototype.map, available on latest browsers:
function valuesToArray(obj) {
return Object.keys(obj).map(function (key) { return obj[key]; });
}
UPDATE: ES2017 introduced the Object.values
method, which does exactly what you want.
Additionally, ES2017 adds another often useful method, Object.entries
. This method returns an array of key-value pairs.
const obj = {
"Mike": 24,
"Peter": 23,
"Simon": 33,
"Tom": 12,
"Frank": 31
};
const values = Object.values(obj);
const entries = Object.entries(obj);
console.log('values:', values);
console.log('entries:', entries);
Use Object.values it will return array.
Object.values(obj) // [24, 23, 33, 12, 31]
There's no built-in way to do this anywhere. The following does what you suggest, and may be "shortened" into more clever functional-programming versions depending on your library, but they'll all have the same efficiency.
function valuesToArray(obj) {
var result = [];
for (var key in obj) {
if (obj.hasOwnProperty(key)) {
result.push(obj[key]);
}
}
return result;
}
With jQuery you could use the each function:
var obj = {
"Mike": 24,
"Peter": 23,
"Simon": 33,
"Tom": 12,
"Frank": 31
}
myArray=new Array();
$.each(obj, function(key, value) {
myArray.push(value);
});
Posting this strictly for fun. Save your downvotes. I'm not recommending it actually be used. ;o)
Example: http://jsfiddle.net/WGpXX/
var arr = eval( '[' +
JSON.stringify(obj)
.slice(1,-1)
.replace(/"[^"]+":/g,'')
+ ']');
Technically works in this simple case.
Using the Underscore lib try:
function valuesToArray(o) {
return _.pairs(o);
}
var obj = {
"Mike": 24,
"Peter": 23
//...
},
result = valuesToArray(obj);
Then the result is [ ["Mike", 24], ["Peter", 23] ];
More detail on the pairs method here: http://underscorejs.org/#pairs
Try this:
var obj = { "Mike": 24, "Peter": 23, "Simon": 33, "Tom": 12, "Frank": 31 } ;
var arr = []
for(var a in obj)
{
var val = obj[a];
arr.push(val);
}
alert(arr.length)
Some libraries have something to do this (such as prototype's "values" function), but they're really just wrappers around a function that loops over and returns the values of the object.
http://www.prototypejs.org/api/object/values
Using bob.js this can be done pretty simply:
function valuesToArray(obj) {
return bob.collections.extensions.toArray.call(obj);
}
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