Sorting Objects By Property Values

How to implement the following scenario using Javascript only: Create a car object with properties (top speed, brand, etc.) Sort a list of cars ordered by those properties

Solution 1:

javascript has the sort function which can take another function as parameter - that second function is used to compare two elements.

Example:

cars = [

    {
        name: "Honda",
        speed: 80
    },

    {
        name: "BMW",
        speed: 180
    },

    {
        name: "Trabi",
        speed: 40
    },

    {
        name: "Ferrari",
        speed: 200
    }
]


cars.sort(function(a, b) { 
    return a.speed - b.speed;
})

for(var i in cars)
    document.writeln(cars[i].name) // Trabi Honda BMW Ferrari 

ok, from your comment i see that you're using the word 'sort' in a wrong sense. In programming "sort" means "put things in a certain order", not "arrange things in groups". The latter is much simpler - this is just how you "sort" things in the real world

• make two empty arrays ("boxes")
• for each object in your list, check if it matches the criteria
• if yes, put it in the first "box"
• if no, put it in the second "box"

Solution 2:

Example.

This runs on cscript.exe, on windows.

// define the Car class
(function() {
    // makeClass - By John Resig (MIT Licensed)// Allows either new User() or User() to be employed for construction.functionmakeClass(){
        returnfunction(args){
            if ( thisinstanceofarguments.callee ) {
                if ( typeofthis.init == "function" )
                    this.init.apply( this, (args && args.callee) ? args : arguments );
            } elsereturnnewarguments.callee( arguments );
        };
    }

    Car = makeClass();

    Car.prototype.init = function(make, model, price, topSpeed, weight) {
        this.make = make;
        this.model = model;
        this.price = price;
        this.weight = weight;
        this.topSpeed = topSpeed;
    };
})();


// create a list of carsvar autos = [
    newCar("Chevy", "Corvair", 1800, 88, 2900),
    newCar("Buick", "LeSabre", 31000, 138, 3700),
    newCar("Toyota", "Prius", 24000, 103, 3200),
    newCar("Porsche", "911", 92000, 155, 3100),
    newCar("Mercedes", "E500", 67000, 145, 3800),
    newCar("VW", "Passat", 31000, 135, 3700)
];

// a list of sorting functionsvar sorters = {
    byWeight : function(a,b) {
        return (a.weight - b.weight);
    },
    bySpeed : function(a,b) {
        return (a.topSpeed - b.topSpeed);
    },
    byPrice : function(a,b) {
        return (a.price - b.price);
    },
    byModelName : function(a,b) {
        return ((a.model < b.model) ? -1 : ((a.model > b.model) ? 1 : 0));
    },
    byMake : function(a,b) {
        return ((a.make < b.make) ? -1 : ((a.make > b.make) ? 1 : 0));
    }
};

functionsay(s) {WScript.Echo(s);}

functionshow(title)
{
    say ("sorted by: "+title);
    for (var i=0; i < autos.length; i++) {
        say("  " + autos[i].model);
    }
    say(" ");
}

autos.sort(sorters.byWeight);
show("Weight");

autos.sort(sorters.byModelName);
show("Name");

autos.sort(sorters.byPrice);
show("Price");

You can also make a general sorter.

var byProperty = function(prop) {
    returnfunction(a,b) {
        if (typeof a[prop] == "number") {
            return (a[prop] - b[prop]);
        } else {
            return ((a[prop] < b[prop]) ? -1 : ((a[prop] > b[prop]) ? 1 : 0));
        }
    };
};

autos.sort(byProperty("topSpeed"));
show("Top Speed");

Solution 3:

I have wrote this simple function for myself:

functionsortObj(list, key) {
    functioncompare(a, b) {
        a = a[key];
        b = b[key];
        var type = (typeof(a) === 'string' ||
                    typeof(b) === 'string') ? 'string' : 'number';
        var result;
        if (type === 'string') result = a.localeCompare(b);
        else result = a - b;
        return result;
    }
    return list.sort(compare);
}

for example you have list of cars:

var cars= [{brand: 'audi', speed: 240}, {brand: 'fiat', speed: 190}];
var carsSortedByBrand = sortObj(cars, 'brand');
var carsSortedBySpeed = sortObj(cars, 'speed');

Solution 4:

Here's a short example, that creates and array of objects, and sorts numerically or alphabetically:

// Create Objects Arrayvar arrayCarObjects = [
{brand: "Honda",        topSpeed: 45},
{brand: "Ford",         topSpeed: 6},
{brand: "Toyota",       topSpeed: 240},
{brand: "Chevrolet",    topSpeed: 120},
{brand: "Ferrari",      topSpeed: 1000}
];

// Sort Objects Numerically

arrayCarObjects.sort((a, b) => (a.topSpeed - b.topSpeed));

// Sort Objects Alphabetically

arrayCarObjects.sort((a, b) => (a.brand > b.brand) ? 1 : -1);

Solution 5:

Let us say we have to sort a list of objects in ascending order based on a particular property, in this example lets say we have to sort based on the "name" property, then below is the required code :

var list_Objects = [{"name"="Bob"},{"name"="Jay"},{"name"="Abhi"}];
Console.log(list_Objects);   //[{"name"="Bob"},{"name"="Jay"},{"name"="Abhi"}]
    list_Objects.sort(function(a,b){
        return a["name"].localeCompare(b["name"]); 
    });
Console.log(list_Objects);  //[{"name"="Abhi"},{"name"="Bob"},{"name"="Jay"}]