


Analysis of array sort and reverse usage in Javascript_javascript skills
The examples in this article describe the usage of array sort and reverse in Javascript. Share it with everyone for your reference. The specific analysis is as follows:
Thesort() method is used to sort the elements of an array.
reverse() reverses the order of the elements in the array
First let’s try the following code:
values.reverse();
console.log(values);
What will the output be:
[ 10, 15, 5, 0, 1 ]
reverse() is simply to reverse the array, so the next thing I want to complain about is sort()
values.sort();
console.log(values);
The output result of this function is actually:
[ 0, 1, 10, 15, 5 ]
What’s going on?
Actually, will use toString() transformation inside the sort() function, and String comparison is through ASCII, so if we need to sort, it is better to write a sort() ourselves.
function compare(value1, value2) {
If (value1 < value2) {
return -1;
} else if (value1 > value2) {
Return 1;
} else {
return 0;
}
}
values.sort(compare);
console.log(values);
If you swap -1 and 1, you can sort in reverse order.
Current output:
[ 0, 1, 5, 10, 15 ]
A simpler way to write it is to use return value2 - value1;
inside compare()I hope this article will be helpful to everyone’s JavaScript programming design.

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