Sample query:
I’ve got the following objects using AJAX and stored them in an array:
var homes = [
{
"h_id": "3",
"city": "Dallas",
"state": "TX",
"zip": "75201",
"price": "162500"
}, {
"h_id": "4",
"city": "Bevery Hills",
"state": "CA",
"zip": "90210",
"price": "319250"
}, {
"h_id": "5",
"city": "New York",
"state": "NY",
"zip": "00010",
"price": "962500"
}
];
How do I create a function to sort the objects by the price
property in ascending or descending order using JavaScript only?
How to sort array of objects by property values in JavaScript?
This can be done by writing your own comparison function and it’s easy enough to write your own comparison function:
function compare( a, b ) {
if ( a.last_nom < b.last_nom ){
return -1;
}
if ( a.last_nom > b.last_nom ){
return 1;
}
return 0;
}
objs.sort( compare );
Or inline (c/o Marco Demaio):
objs.sort((a,b) => (a.last_nom > b.last_nom) ? 1 : ((b.last_nom > a.last_nom) ? -1 : 0))
You can also use the following method.
Sort homes by price in ascending order:
homes.sort(function(a, b) {
return parseFloat(a.price) - parseFloat(b.price);
});
Or after the ES6 version:
homes.sort((a, b) => parseFloat(a.price) - parseFloat(b.price));
Some documentation can be found here.
For descending order, you may use
homes.sort((a, b) => parseFloat(b.price) - parseFloat(a.price));
Answer #2:
Here’s a more flexible version, which allows you to create reusable sort functions, and sort by any field.
const sort_by = (field, reverse, primer) => {
const key = primer ?
function(x) {
return primer(x[field])
} :
function(x) {
return x[field]
};
reverse = !reverse ? 1 : -1;
return function(a, b) {
return a = key(a), b = key(b), reverse * ((a > b) - (b > a));
}
}
//Now you can sort by any field at will...
const homes=[{h_id:"3",city:"Dallas",state:"TX",zip:"75201",price:"162500"},{h_id:"4",city:"Bevery Hills",state:"CA",zip:"90210",price:"319250"},{h_id:"5",city:"New York",state:"NY",zip:"00010",price:"962500"}];
// Sort by price high to low
console.log(homes.sort(sort_by('price', true, parseInt)));
// Sort by city, case-insensitive, A-Z
console.log(homes.sort(sort_by('city', false, (a) => a.toUpperCase()
)));
You can also create a dynamic sort function that sorts objects by the value that you pass:
function dynamicSort(property) {
var sortOrder = 1;
if(property[0] === "-") {
sortOrder = -1;
property = property.substr(1);
}
return function (a,b) {
/* next line works with strings and numbers,
* and you may want to customize it to your needs
*/
var result = (a[property] < b[property]) ? -1 : (a[property] > b[property]) ? 1 : 0;
return result * sortOrder;
}
}
So you can have an array of objects like this:
var People = [
{Name: "Name", Surname: "Surname"},
{Name:"AAA", Surname:"ZZZ"},
{Name: "Name", Surname: "AAA"}
];
…and it will work when you do:
People.sort(dynamicSort("Name"));
People.sort(dynamicSort("Surname"));
People.sort(dynamicSort("-Surname"));
Actually, this already answers the question. The below part is written because many people contacted me, complaining that it doesn’t work with multiple parameters.
Multiple Parameters
You can use the function below to generate sort functions with multiple sort parameters.
function dynamicSortMultiple() {
/*
* save the arguments object as it will be overwritten
* note that arguments object is an array-like object
* consisting of the names of the properties to sort by
*/
var props = arguments;
return function (obj1, obj2) {
var i = 0, result = 0, numberOfProperties = props.length;
/* try getting a different result from 0 (equal)
* as long as we have extra properties to compare
*/
while(result === 0 && i < numberOfProperties) {
result = dynamicSort(props[i])(obj1, obj2);
i++;
}
return result;
}
}
Which would enable you to do something like this:
People.sort(dynamicSortMultiple("Name", "-Surname"));
Subclassing Array
For the lucky among us who can use ES6, which allows extending the native objects:
class MyArray extends Array {
sortBy(...args) {
return this.sort(dynamicSortMultiple(...args));
}
}
That would enable this:
MyArray.from(People).sortBy("Name", "-Surname");
Answer #3:
To sort it you need to create a comparator function taking two arguments. Then call the sort function with that comparator function as follows:
// a and b are object elements of your array
function mycomparator(a,b) {
return parseInt(a.price, 10) - parseInt(b.price, 10);
}
homes.sort(mycomparator);
If you want to sort ascending switch the expressions on each side of the minus sign.
Answer #4:
For string sorting in case, someone needs it,
const dataArr = {
"hello": [{
"id": 114,
"keyword": "zzzzzz",
"region": "Sri Lanka",
"supportGroup": "administrators",
"category": "Category2"
}, {
"id": 115,
"keyword": "aaaaa",
"region": "Japan",
"supportGroup": "developers",
"category": "Category2"
}]
};
const sortArray = dataArr['hello'];
console.log(sortArray.sort((a, b) => {
if (a.region < b.region)
return -1;
if (a.region > b.region)
return 1;
return 0;
}));
Answer #5:
If you have an ES6 compliant browser you can use:
The difference between ascending and descending sort order is the sign of the value returned by your compare function:
var ascending = homes.sort((a, b) => Number(a.price) - Number(b.price));
var descending = homes.sort((a, b) => Number(b.price) - Number(a.price));
Here’s a working code snippet:
var homes = [{
"h_id": "3",
"city": "Dallas",
"state": "TX",
"zip": "75201",
"price": "162500"
}, {
"h_id": "4",
"city": "Bevery Hills",
"state": "CA",
"zip": "90210",
"price": "319250"
}, {
"h_id": "5",
"city": "New York",
"state": "NY",
"zip": "00010",
"price": "962500"
}];
homes.sort((a, b) => Number(a.price) - Number(b.price));
console.log("ascending", homes);
homes.sort((a, b) => Number(b.price) - Number(a.price));
console.log("descending", homes);
Sorting an array of objects by property values- Answer #6:
You want to sort it in Javascript, right? What you want is the sort()
function. In this case you need to write a comparator function and pass it to sort()
, so something like this:
function comparator(a, b) {
return parseInt(a["price"], 10) - parseInt(b["price"], 10);
}
var json = { "homes": [ /* your previous data */ ] };
console.log(json["homes"].sort(comparator));
Your comparator takes one of each of the nested hashes inside the array and decides which one is higher by checking the “price” field.
Answer #7:
I recommend GitHub: Array sortBy – a best implementation of sortBy
method which uses the Schwartzian transform
But for now, we are going to try this approach Gist: sortBy-old.js.
Let’s create a method to sort arrays being able to arrange objects by some property.
Creating the sorting function
var sortBy = (function () {
var toString = Object.prototype.toString,
// default parser function
parse = function (x) { return x; },
// gets the item to be sorted
getItem = function (x) {
var isObject = x != null && typeof x === "object";
var isProp = isObject && this.prop in x;
return this.parser(isProp ? x[this.prop] : x);
};
/**
* Sorts an array of elements.
*
* @param {Array} array: the collection to sort
* @param {Object} cfg: the configuration options
* @property {String} cfg.prop: property name (if it is an Array of objects)
* @property {Boolean} cfg.desc: determines whether the sort is descending
* @property {Function} cfg.parser: function to parse the items to expected type
* @return {Array}
*/
return function sortby (array, cfg) {
if (!(array instanceof Array && array.length)) return [];
if (toString.call(cfg) !== "[object Object]") cfg = {};
if (typeof cfg.parser !== "function") cfg.parser = parse;
cfg.desc = !!cfg.desc ? -1 : 1;
return array.sort(function (a, b) {
a = getItem.call(cfg, a);
b = getItem.call(cfg, b);
return cfg.desc * (a < b ? -1 : +(a > b));
});
};
}());
Setting unsorted data
var data = [
{date: "2011-11-14T16:30:43Z", quantity: 2, total: 90, tip: 0, type: "tab"},
{date: "2011-11-14T17:22:59Z", quantity: 2, total: 90, tip: 0, type: "Tab"},
{date: "2011-11-14T16:28:54Z", quantity: 1, total: 300, tip: 200, type: "visa"},
{date: "2011-11-14T16:53:41Z", quantity: 2, total: 90, tip: 0, type: "tab"},
{date: "2011-11-14T16:48:46Z", quantity: 2, total: 90, tip: 0, type: "tab"},
{date: "2011-11-14T17:25:45Z", quantity: 2, total: 200, tip: 0, type: "cash"},
{date: "2011-11-31T17:29:52Z", quantity: 1, total: 200, tip: 100, type: "Visa"},
{date: "2011-11-14T16:58:03Z", quantity: 2, total: 90, tip: 0, type: "tab"},
{date: "2011-11-14T16:20:19Z", quantity: 2, total: 190, tip: 100, type: "tab"},
{date: "2011-11-01T16:17:54Z", quantity: 2, total: 190, tip: 100, type: "tab"},
{date: "2011-11-14T17:07:21Z", quantity: 2, total: 90, tip: 0, type: "tab"},
{date: "2011-11-14T16:54:06Z", quantity: 1, total: 100, tip: 0, type: "Cash"}
];
Using it
Arrange the array, by "date"
as String
// sort by @date (ascending)
sortBy(data, { prop: "date" });
// expected: first element
// { date: "2011-11-01T16:17:54Z", quantity: 2, total: 190, tip: 100, type: "tab" }
// expected: last element
// { date: "2011-11-31T17:29:52Z", quantity: 1, total: 200, tip: 100, type: "Visa"}
If you want to ignore case sensitive, set the parser
callback:
// sort by @type (ascending) IGNORING case-sensitive
sortBy(data, {
prop: "type",
parser: (t) => t.toUpperCase()
});
// expected: first element
// { date: "2011-11-14T16:54:06Z", quantity: 1, total: 100, tip: 0, type: "Cash" }
// expected: last element
// { date: "2011-11-31T17:29:52Z", quantity: 1, total: 200, tip: 100, type: "Visa" }
If you want to convert the "date"
field as Date
type:
// sort by @date (descending) AS Date object
sortBy(data, {
prop: "date",
desc: true,
parser: (d) => new Date(d)
});
// expected: first element
// { date: "2011-11-31T17:29:52Z", quantity: 1, total: 200, tip: 100, type: "Visa"}
// expected: last element
// { date: "2011-11-01T16:17:54Z", quantity: 2, total: 190, tip: 100, type: "tab" }
Examples to sort array of objects by string property value:
#1:
In ES6/ES2015 or later you can do this way:
objs.sort((a, b) => a.last_nom.localeCompare(b.last_nom));
Prior to ES6/ES2015
objs.sort(function(a, b) {
return a.last_nom.localeCompare(b.last_nom)
});
#2:
Use underscore, it’s small and awesome:
sortBy_.sortBy(list, iterator, [context]) Returns a sorted copy of list, ranked in ascending order by the results of running each value through iterator. Iterator may also be the string name of the property to sort by (eg. length).
var objs = [
{ first_nom: 'Lazslo',last_nom: 'Jamf' },
{ first_nom: 'Pig', last_nom: 'Bodine' },
{ first_nom: 'Pirate', last_nom: 'Prentice' }
];
var sortedObjs = _.sortBy( objs, 'first_nom' );
#3:
If you have duplicate last names you might sort those by first name-
obj.sort(function(a,b){
if(a.last_nom< b.last_nom) return -1;
if(a.last_nom >b.last_nom) return 1;
if(a.first_nom< b.first_nom) return -1;
if(a.first_nom >b.first_nom) return 1;
return 0;
});
Hope you learned something from this post.
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