slice method
The slice method slices and
returns the specified portion of an
array. The array itself remains
unmodified.
The first parameter specifies the number of the array element where the cutting starts, and the second parameter is the number of the element where the cutting ends (the element with this number will not be included in the cut part). The second parameter is optional. If it is not specified, the subarray will be taken from the element specified in the first parameter to the end of the array.
It can also take negative values. In
this case, the element where the cutting
ends is counted from the end of
the array. The last element in this
case will have the number -1.
Syntax
array.slice(where to start, [where to end]);
Example
Let's slice array elements from zero to the second, not inclusive (the second one will not be cut out):
let arr = ['a', 'b', 'c', 'd', 'e'];
let sub = arr.slice(0, 2);
console.log(sub);
The code execution result:
['a', 'b']
Example
Let's cut the elements from the first to the end of an array. To do this, we don't set the second parameter:
let arr = ['a', 'b', 'c', 'd', 'e'];
let sub = arr.slice(1);
console.log(sub);
The code execution result:
['b', 'c', 'd', 'e']
Example
Let's cut out the elements from the
second to the second to last (-1
points to the second to last element and it
will not be included in the extracted
part):
let arr = ['a', 'b', 'c', 'd', 'e'];
let sub = arr.slice(1, -1);
console.log(sub);
The code execution result:
['b', 'c', 'd']
The advantage of this method is that the cut will always be part of an array, not including the last element, regardless of the size of the array.
