Array of Function

Introduction:

The array.of() function is an inbuilt function in JavaScript that creates a new array instance with variables present as the argument of the function.

Syntax:

Array.of(element0, element1, ....)

Parameters: Parameters present are element0, element1, …. which are basically an element for which the array creation is done. Return Value: It simply returns a new Array instance.

Examples:

Input: Array.of(10, 20, 30)
Output: > Array [10, 20, 30]

Explanation: Here in input arguments of the array.of() function is numbers converted into an array containing the same argument shown in the output.

Input: Array.of("Ram","Geeta")
Output: > Array ["Ram", "Geeta"]

Explanation: Here in input arguments of the array.of() function is string converted into an array containing the same argument shown in the output.

Let’s see JavaScripts program on Array.of() function:

<script>

  //  Here the Array.of() method creates a new Array instance with
  // a variable number of arguments, regardless of
  // number or type of the arguments.
  console.log(Array.of(0, 0, 0));
  console.log(Array.of(11, 21, 33));
  console.log(Array.of("Sujall","Vvarsha"));
  console.log(Array.of('iwritecode'));
  console.log(Array.of(2,3,4,'Husky'));
</script>

Output:

> Array [0, 0, 0]
> Array [11, 21, 33]
> Array ["Sujall", "Vvarsha"]
> Array ["iwritecode"]
> Array [2, 3, 4, "Husky"]

Application:

Whenever we need to get elements of an array that time we take the help of the Array.of( ) method in JavaScript.

<script>
  console.log(Array.of(['Vvarsha', 'Sujall', 'Krishna', 'Shrishti']));
</script>

Output:

> Array [Array ["Vvarsha", "Sujall", "Krishna", "Shrishti"]]

Polyfill : Polyfills provide a way to implement new features into old browsers that do not support the newest updated version of JavaScript code.

Array.of( ) function does not support by Internet Explorer browser. As a developer, it’s your responsibility to provide a code that runs everywhere ( browser in this case ).

So let’s see how to create a polyfill for Array.of( )

Steps :

Check if Array.of( ) function is supported in browser or not. Now create a function expression named Array.of( ) . This function takes the items of the array. Now create an array and push all the argument items into it. Now return the array created by you.

<script>
 // check if Array.of( ) feature present in your browser or not
 if(!Array.of){

     // Create a function
    Array.of = function() {
        let newArr = [];

        // Pushing all the arguments into newArr
         for(let items in arguments){
            newArr.push(arguments[items]);
        }
        // return the array
        return newArr;
     }
 }
 </script>

Output :

> Array.of(1, 2, 3, 4, 5, 6)
> [1, 2, 3, 4, 5, 6]

> Array.of("John", "Doe", "Smith", "Ram")
> ["John", "Doe", "Smith", "Ram"]

Supported Browser:

1. Chrome 45 and above
2. Edge 12 and above
3. Firefox 25 and above
4. Opera 26 and above
5. Safari 9 and above