JavaScript - Array join() Method
The JavaScript Array join() method is used to concatenate the array elements with a specified separator and returns the result as a string.
- If no separator is specified, the array elements will be separated by (,) comma by default.
- This method does not change the original array instead, it returns a new string as a result.
- If the array has only one item, then the value will be returned without a separator.
Syntax
Following is the syntax of JavaScript Array join() method −
array.join(separator);
Parameters
This method accepts only one parameter. The same is described below −
- The "separator" is a string that separates the elements in the resulting string. By default, it separated with (,) comma.
Return value
A string representing the elements of the array joined by the specified separator.
Examples
Example 1
If we do not pass any separator to the JavaScript Array copyWithin() method, it will separate the elements with (,) comma by default.
<html>
<body>
<p id="demo"></p>
<script>
const animals = ["Lion", "Chetaah", "Tiger", "Elephant", "Dinosaur"];
let result = animals.join();
document.getElementById("demo").innerHTML = result;
</script>
</body>
</html>
Output
As we can see the output, all the elements in the array are seperated with (,) comma.
Lion,Chetaah,Tiger,Elephant,Dinosaur
Example 2
Here, we are passing an empty string as a parameter to this function. So that, it will return the elements without a (,) comma and no space in between them −
<html>
<body>
<p id="demo"></p>
<script>
const animals = ["Lion", "Chetaah", "Tiger", "Elephant", "Dinosaur"];
let result = animals.join("");
document.getElementById("demo").innerHTML = result;
</script>
</body>
</html>
Output
After executing the above program, the array elements will be separated with no space in between them.
LionChetaahTigerElephantDinosaur
Example 3
Here, we are passing "and" as a separator to this function. So that, the array elements will be separated by "and" −
<html>
<body>
<p id="demo"></p>
<script>
const animals = ["Lion", "Chetaah", "Tiger", "Elephant", "Dinosaur"];
let result = animals.join(" and ");
document.getElementById("demo").innerHTML = result;
</script>
</body>
</html>
Output
After executing the above program, the array elements will be separated by "and".
Lion and Chetaah and Tiger and Elephant and Dinosaur