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JavaScript: Get the first element of an array

JavaScript Array: Exercise-1 with Solution

Write a JavaScript function to check whether an 'input' is an array or not.

Test Data:
console.log(is_array('w3resource'));
console.log(is_array([1, 2, 4, 0]));
false
true

Sample Solution:

HTML Code:

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>JS Bin</title>
</head>
<body>
</body>
</html>

JavaScript Code:

var is_array = function(input) {
  if (toString.call(input) === "[object Array]")
    return true;
  return false;   
    };
console.log(is_array('w3resource'));
console.log(is_array([1, 2, 4, 0]));

Sample Output:

false
true

Flowchart:

Flowchart: JavaScript: Display the colors entered in an array by a specific format

ES6 Version:

var is_array = input => {
  if (toString.call(input) === "[object Array]")
    return true;
  return false;   
    };
console.log(is_array('w3resource'));
console.log(is_array([1, 2, 4, 0]));

Live Demo:

See the Pen JavaScript - Get the first element of an array- array-ex-1 by w3resource (@w3resource) on CodePen.


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JavaScript: Tips of the Day

How do I redirect to another webpage?

window.location.replace(...) is better than using window.location.href, because replace() does not keep the originating page in the session history, meaning the user won't get stuck in a never-ending back-button fiasco.

If you want to simulate someone clicking on a link, use location.href

If you want to simulate an HTTP redirect, use location.replace.

// similar behavior as an HTTP redirect
window.location.replace("http://stackoverflow.com");

// similar behavior as clicking on a link
window.location.href = "http://stackoverflow.com";

Ref: https://bit.ly/37JdWH8