JavaScript Array: get "range" of items
Is there an equivalent for ruby's array[n..m]
in JavaScript?
For example:
>> a = ['a','b','c','d','e','f','g']
>> a[0..2]
=> ['a','b','c']
Use the array.slice(begin [, end])
function.
var a = ['a','b','c','d','e','f','g'];
var sliced = a.slice(0, 3); //will contain ['a', 'b', 'c']
The last index is non-inclusive; to mimic ruby's behavior you have to increment the end
value. So I guess slice
behaves more like a[m...n]
in ruby.
The second argument in slice
is optional, too:
var fruits = ['apple','banana','peach','plum','pear'];
var slice1 = fruits.slice(1, 3); //banana, peach
var slice2 = fruits.slice(3); //plum, pear
You can also pass a negative number, which selects from the end of the array:
var slice3 = fruits.slice(-3); //peach, plum, pear
Here's the W3 Schools reference link.
a.slice(0, 3)
Would be the equivalent of your function in your example.
https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/slice