sort method
The sort method sorts an array
in lexicographic order and returns the
already modified array. As an optional
parameter, you can specify your own
function for sorting.
Syntax
array.sort([function]);
Example
Let's sort an array:
let arr = ['d', 'b', 'a', 'c'];
console.log(arr.sort());
The code execution result:
['a', 'b', 'c', 'd']
Example
Let's sort an array with numbers:
let arr = [4, 1, 7, 2];
console.log(arr.sort());
The code execution result:
[1, 2, 4, 7]
Example
Let's add numbers to an array and sort it:
let arr = [1, 123, 2, 4, 111, 7];
console.log(arr.sort());
As a result of the code execution, we will see that the numbers are not arranged in ascending order, but in lexicographic order, i.e. numbers are compared to each other like strings. In this case, the comparison is carried out for each character, whether the code of the first character is greater than the code of the neighboring one, etc. Result:
[1, 111, 123, 2, 4, 7]
Example
Now let's sort an array using a function
in which we write a condition - if the
first parameter is greater than the second,
then we rearrange it (for this, any positive
number is in return). Otherwise,
no rearrangement is required and we specify
0 or any negative number:
let arr = [1, 123, 2, 4, 111, 7];
arr.sort(function(a, b) {
if (a > b) {
return 1;
} else {
return -1;
}
});
console.log(arr);
The code execution result:
[1, 2, 4, 7, 111, 123]
Example
Let's shorten the code for convenience in our function from the previous example:
let arr = [1, 123, 2, 4, 111, 7];
arr.sort(function(a, b) {
return a - b;
});
console.log(arr);
The code execution result:
[1, 2, 4, 7, 111, 123]
Example
And now, using a function, we sort an array in descending order:
let arr = [1, 123, 2, 4, 111, 7];
arr.sort(function(a, b) {
return b - a;
});
console.log(arr);
The code execution result:
[123, 111, 7, 4, 2, 1]
Example
Let's sort an array of objects by
the key 'one' in ascending order:
let arr = [
{one: 1, two: 2},
{one: 7, two: 1},
{one: 3, two: 3}
];
arr.sort(function(a, b) {
return a.one - b.one;
});
console.log(arr);
The code execution result:
[
{one: 1, two: 2},
{one: 3, two: 3},
{one: 7, two: 1}
]
Example
Now let's sort an array of objects
by the key 'two':
let arr = [
{one: 1, two: 2},
{one: 7, two: 1},
{one: 3, two: 3}
];
arr.sort(function(a, b) {
return a.two - b.two;
});
console.log(arr);
The code execution result:
[
{one: 7, two: 1},
{one: 1, two: 2},
{one: 3, two: 3}
]
Example
Let's check if an array has changed
after applying the sort method:
let arr = ['b', 'a', 'd', 'c'];
let res = arr.sort();
console.log(arr);
The code execution result:
['a', 'b', 'c', 'd']
See also
-
the
filtermethod
that allows you to filter the elements of an array
