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JavaScript join() Method: Array Object

Description

The join() method is used to join all elements of an array into a string. The elements are separated by a specified separator.

w3r video tutorialsWatch JavaScript array object join method video tutorial.

Version

Implemented in JavaScript 1.1

Syntax

join(separator)

Parameters

separator: Specifies a string to separate each element of the array. Default separator for the join() method is comma(',').

Example:

In the following web document there is an array called fruits with four elements, join() method is used in different ways : using the default separator, then a comma with a space separator, and then a hyphen separator.

HTML Code

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf8" />
<title>JavaScript join() method Example-1</title>
<style type="text/css">
h1 {color:red}
</style>
</head>
<body>
<h1>JavaScript : join() method</h1>
<script src="array-join-example1.js">
</script>
</body>
</html>

JS Code

var fruits = new Array("Orange", "Apple", "Banana", "Chery");
var fruitslist1=fruits.join();
var newParagraph = document.createElement("p");
var newText = document.createTextNode("Fruits List : " + fruitslist1 ); 
newParagraph.appendChild(newText);
document.body.appendChild(newParagraph);

var fruitslist2=fruits.join(', ');
var newParagraph1 = document.createElement("p");
var newText1 = document.createTextNode("Fruits List : " + fruitslist2); 
newParagraph1.appendChild(newText1); 
document.body.appendChild(newParagraph1); 

var fruitslist3=fruits.join('-');
var newParagraph2 = document.createElement("p");
var newText2 = document.createTextNode("Fruits List : " + fruitslist3);
newParagraph2.appendChild(newText2);
document.body.appendChild(newParagraph2);

View the example in the browser

Practice the example online

JavaScript join() method Example-1

See also :

JavaScript Core objects, methods, properties.

Previous: JavaScript concat() Method : Array Object
Next: JavaScript pop() Method: Array Object



JavaScript: Tips of the Day

Returns 1 if the array is sorted in ascending order, -1 if it is sorted in descending order or 0 if it is not sorted

Example:

const tips_Sorted = arr => {
  let direction = -(arr[0] - arr[1]);
  for (let [i, val] of arr.entries()) {
    direction = !direction ? -(arr[i - 1] - arr[i]) : direction;
    if (i === arr.length - 1) return !direction ? 0 : direction / Math.abs(direction);
    else if ((val - arr[i + 1]) * direction > 0) return 0;
  }
};
console.log(tips_Sorted([0, 1, 2, 2]));
console.log(tips_Sorted([5, 7, 3]));
console.log(tips_Sorted([8, 6, 4]));

Output:

1
0
-1