Sorting an Array
The sort() method sorts an array alphabetically:
Reversing an Array
The reverse() method reverses the elements in an array:
By combining sort() and reverse(), you can sort an array in descending order:
JavaScript Array toSorted() Method
ES2023 added the toSorted() method as a safe way to sort an array without altering the original array.
The difference between toSorted() and sort() is that the first method creates a new array, keeping the original array unchanged, while the last method alters the original array.
JavaScript Array toReversed() Method
ES2023 added the toReversed() method as a safe way to reverse an array without altering the original array.
The difference between toReversed() and reverse() is that the first method creates a new array, keeping the original array unchanged, while the last method alters the original array
Numeric Sort
By default, the sort() function sorts values as strings.
This works well for strings ("Apple" comes before "Banana").
If numbers are sorted as strings, "25" is bigger than "100", because "2" is bigger than "1".
Because of this, the sort() method will produce incorrect result when sorting numbers.
You can fix this by providing a compare function:
Use the same trick to sort an array descending
The Compare Function
The purpose of the compare function is to define an alternative sort order.
The compare function should return a negative, zero, or positive value, depending on the arguments
When the sort() function compares two values, it sends the values to the compare function, and sorts the values according to the returned (negative, zero, positive) value.
If the result is negative, a is sorted before b.
If the result is positive, b is sorted before a.
If the result is 0, no changes are done with the sort order of the two values
Example:
The compare function compares all the values in the array, two values at a time (a, b).
When comparing 40 and 100, the sort() method calls the compare function(40, 100).
The function calculates 40 - 100 (a - b), and since the result is negative (-60), the sort function will sort 40 as a value lower than 100
Sorting an Array in Random Order
Using a sort function, like explained above, you can sort an numeric array in random order
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