The<span style="color:#cf2e2e" class="tadv-color"> slice()</span>
method is part of JavaScript Array class. It extract certain elements from an array and returns a new array.
There are different ways to select elements using <span style="color:#cf2e2e" class="tadv-color">slice()</span>
in JavaScript.
The<span style="color:#cf2e2e" class="tadv-color"> slice()</span>
method takes two parameters – start index and the end index of an array. It does not include the last element while returning a new array.
Examples of slice() method
In these examples, we will extract from an array using different forms of <span style="color:#cf2e2e" class="tadv-color">slice()</span>
syntax.
// declare the array
myArray = ["one", "two", "three", "four"];
// only start index is mentioned
var result1 = myArray.slice(2);
console.log(result1);
The <span style="color:#cf2e2e" class="tadv-color">slice() </span>
method will start extracting from index 2 and since the end index is not mentioned, it will extract the rest of elements from the array. The result of the above program is given below.
["three", "four"]
In the next example, we will mention both start as well as end index value. Here is the example script.
// declare the array
myArray = ["one", "two", "three", "four"];
// both start index and end index is mentioned
var result = myArray.slice(1,3);
console.log(result);
The array start with index <span style="color:#cf2e2e" class="tadv-color">1 </span>
of the array. At index <span style="color:#cf2e2e" class="tadv-color">1</span>
, the element is “two” and ends with index 2
because the end value 3 in <span style="color:#cf2e2e" class="tadv-color">slice(1,3)</span>
is not included.
The output is as follows.
Sometimes you want to extract elements starting from end to start of the array. It is also known as negative index.
// declare the array
myArray = ["one", "two", "three", "four"];
// negative index starts from -1
var result = myArray.slice(-3,-1);
document.body.innerHTML = result;
The negative index starts from <span style="color:#cf2e2e" class="tadv-color">-1</span>
. The element at<span style="color:#cf2e2e" class="tadv-color"> -1 </span>
position is “<span style="color:#cf2e2e" class="tadv-color">three</span>
” in the above example array.
You cannot use index <span style="color:#cf2e2e" class="tadv-color">0 </span>
because it is a positive index and starts from beginning of the array.
The output of the above code is as follows.
two,three