如何将数组放入另一个数组？

Question

Guys can u help me? I wanna divide an array that is inside an array into another array.

For example I need to make it like this:

var car = [['mazda','red','at'],['honda','blue','at'],['toyota','green','mt']]
var mazda = [] //i want this array contain ['mazda','red','at']
var honda = [] //i want this array contain ['honda','blue','at']
var toyota = [] //i want this array contain ['toyota','green','mt']

Answer 1

Arrays are indexed by number, a positive or null integer.

So the first element is car[0] , the second car[1] , etc.

That's how you would access the Mazda:

var mazda = car[0]

The elements inside the mazda array would similarly be accessed:

var brand = mazda[0]

However, you may want to consider using maps (objects in JavaScript) like:

car = { mazda: { color: 'red', model: 'at' },
        honda: { color: 'blue', model: 'at' },
        toyota: { color: 'green', model: 'mt' } }

Because then you can explicitly access that info:

var mazda = car.mazda

I think it's also less prone to mistakes.

Of course, if you have have multiple mazdas, hondas, toyotas... then you will probably need an array at the top, still. Something like this:

car = [
         { brand: 'mazda', color: 'red', model: 'at' },
         { brand: 'mazda', color: 'green', model: 'at' },
         { brand: 'mazda', color: 'blue', model: 'at' },
         ...
    ]

You may also want to check into JSON which is very often used to transmit data in browsers. It's arrays, objects, values... If you are to program in JavaScript, you'll want to become a master at such.

Answer 2

Well, the literal answer will be

var mazda = car[0]

and so forth. That said, this answer really isn't scalable... if you're learning Javascript, look into objects instead. Then you can do something like:

var cars = { mazda: {color: 'red', otherThing: 'at'}, honda: {... so on ...}};
console.log(cars.mazda.color); //will output 'red'

Answer 3

There are a lot of answers provided now. My opinion is that we can destructure the array and assign it to the variables like this:

 var car = [ ['mazda', 'red', 'at'], ['honda', 'blue', 'at'], ['toyota', 'green', 'mt'] ] let [ mazda, honda, toyota ] = car console.log("Mazda: ", mazda) console.log("Honda: ", honda) console.log("Toyota: ", toyota)

Hope it helps :)

Answer 4

If you know the index of the outer array that you need, the other answers have provided the solution. If you don't know the index, and only know the first element of the inner array that you're looking for, then find is the tool you need:

 var car = [['mazda','red','at'],['honda','blue','at'],['toyota','green','mt']] var mazda = car.find(([make]) => make === 'mazda'); var honda = car.find(([make]) => make === 'honda'); var toyota = car.find(([make]) => make === 'toyota'); console.log(mazda); console.log(honda); console.log(toyota);

Answer 5

I suggest that you read about JavaScript arrays. To help you get started, you can do one of your examples like this:

var mazda = car[0];

You should also learn about objects. Usually arrays should be used for a sequence of similar data. Here 'mazda' , 'red' , and 'at' are attributes of a car, but the order doesn't matter. 'mazda' is the brand, and 'red' is the color. These would make more sense to store in an object.

Answer 6

Use the index of the inner arrays when generating new ones.

var mazda = car[0];
var honda = car[1];
var toyota = car[2];

You can find a lot of good beginner information on Arrays, here .

Answer 7

This is a basic case of multi-dimensional array. You might wanna learn and explore more on arrays .

To solve your case you can solve as:

var mazda = car[0];
var honda = car[1];
var toyota = car[2];

This would have been better solved had you considered using objects. You can learn more about objects here .

Since you have multiple mazdas structure of data you must consider is :

var mazda = [{color: 'red', model: 'at'}, {color: 'green', model: 'at'}];