Web Front-end
JS Tutorial
How to check which browser the current running environment is in JavaScript?
How to check which browser the current running environment is in JavaScript?
Runtime environment is the environment in which code is executed. It tells your code which global objects it can access and also affects its results. JavaScript code can run in different types of environments, some of which are Node.js, Service Workers, or web browsers. So, to start coding with JavaScript, you don’t need to install any additional software. Every web browser comes with a JavaScript engine. You can simply run the script you write in any browser, but it ensures that it follows all the rules of ECMAScript (ES6) functionality.
Here we will detect which runtime environment our code is running in. JavaScript code written in Node.js can also run in any environment, whether it's a browser environment, a Service Worker environment, or the Node.js environment itself. When running code in a different environment, you need to match all the requirements of that environment.
Check whether the runtime environment is a browser
Tocheck whether the runtime environmentpiece of code is a browserThere is no direct way. So, to check the runtime environment, we have to set some conditions to match each environment and check in which environment our code is running. 一段代码是不是浏览器没有直接的方法。因此，要检查运行时环境，我们必须设置一些条件来匹配每个环境，并检查我们的代码在哪个环境中运行。
Syntax
The following is the syntax to check whether the current running environment is a browser-
type of window === "object"
If the above statement returns true, the current running environment is a browser, otherwise no.
Algorithm
- Step 1< /strong> - Check condition typeof window === "object".
- STEP 2 - If true is returned, a message is displayed because the current runtime environment is a window.
- STEP 2 - If false is returned, a message is displayed because the current runtime environment is not a window.
Example
In the following example, we check whether the current running environment is a browser.
<!DOCTYPE html>
<html>
<body>
<div>
<h2 id="Check-if-the-Current-Runtime-Environment-is-Browser">Check if the Current Runtime Environment is Browser</h2>
<p>Click the below button to know if the runtime environment is browser or not</p>
<button onclick = "isBrowser()"> Check Runtime Environment </button>
<p id="result1"></p>
<p id="result2"></p>
</div>
<script>
function isBrowser() {
var text="Runtime environment";
// Check if the runtime environment is a Browser
if (typeof window === "object") {
document.getElementById("result1").innerHTML = text + " is Browser";
} else {
document.getElementById("result2").innerHTML = text + " is NOT Browser";
}
}
</script>
</body>
</html>Check different runtime environments
Each environment has different conditions.
For browser environments< /strong>, the type of window should equal "object".
For node.js environment, we must check 2 conditions. First, check whether the type of process is "object", and whether the type of require is "function" ".
The environment is node.js only if both conditions are true environment.
For Service Worker Environment, we check if the type of the imported script is equal to "function". When it is equal to a function, then only that environment is a service worker thread environment.
Syntax
The following is the syntax to check the runtime environment -
// Condition if Runtime Environment is Node.js typeof process === "object" &&typeof require === " // Condition if Runtime Environment is Service Worker typeof importScripts === "function // Condition if Runtime Environment is Browser typeof window === "object"
Algorithm
- 1st Step - First we check if the runtime environment is Node.js. If true, the correct message is displayed.
- Step 2 - Next we check if the current runtime environment is a Service Worker. If true, the correct message is displayed.
- Step 3 - Finally we check if the runtime environment is a browser. If true, the correct message is displayed.
Example
We can use the following code to check the runtime environment of the program.
<!DOCTYPE html>
<html>
<body>
<div>
<h2 id="Check-the-Current-Runtime-Environment">Check the Current Runtime Environment</h2>
<p>Click the below button to know the runtime environment</p>
<button onclick = "isBrowser()"> Check Runtime Environment </button>
<p id="result1"></p>
<p id="result2"></p>
<p id="result3"></p>
</div>
<script>
function isBrowser() {
var text="Runtime environment";
// Check if the runtime environment is Node.js
if (typeof process === "object" &&typeof require === "function") {
document.getElementById("result1").innerHTML = text + " is node.js"; }
// Check if the runtime environment is a Service worker
if (typeof importScripts === "function") {
document.getElementById("result2").innerHTML = text + " is service worker";
}
// Check if the runtime environment is a Browser
if (typeof window === "object") {
document.getElementById("result3").innerHTML = text + " is Browser";
}
}
</script>
</body>
</html>After clicking the "Check Runtime Environment" button, the screen will show you the output based on the environment in which the program is running.
This feature of JavaScript allows you to write code in any environment and run it in any other different environment, especially in a web browser, while using web pages that run only in a web browser.
Note- The method type used here will give us the data type of the variable, function or method just like it would be in string, number, object, function or any other type of data Type provides the same output.
The above is the detailed content of How to check which browser the current running environment is in JavaScript?. For more information, please follow other related articles on the PHP Chinese website!
Hot AI Tools
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Undress AI Tool
Undress images for free
Clothoff.io
AI clothes remover
Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
What should I do if I encounter garbled code printing for front-end thermal paper receipts?
Apr 04, 2025 pm 02:42 PM
Frequently Asked Questions and Solutions for Front-end Thermal Paper Ticket Printing In Front-end Development, Ticket Printing is a common requirement. However, many developers are implementing...
Demystifying JavaScript: What It Does and Why It Matters
Apr 09, 2025 am 12:07 AM
JavaScript is the cornerstone of modern web development, and its main functions include event-driven programming, dynamic content generation and asynchronous programming. 1) Event-driven programming allows web pages to change dynamically according to user operations. 2) Dynamic content generation allows page content to be adjusted according to conditions. 3) Asynchronous programming ensures that the user interface is not blocked. JavaScript is widely used in web interaction, single-page application and server-side development, greatly improving the flexibility of user experience and cross-platform development.
Who gets paid more Python or JavaScript?
Apr 04, 2025 am 12:09 AM
There is no absolute salary for Python and JavaScript developers, depending on skills and industry needs. 1. Python may be paid more in data science and machine learning. 2. JavaScript has great demand in front-end and full-stack development, and its salary is also considerable. 3. Influencing factors include experience, geographical location, company size and specific skills.
How to merge array elements with the same ID into one object using JavaScript?
Apr 04, 2025 pm 05:09 PM
How to merge array elements with the same ID into one object in JavaScript? When processing data, we often encounter the need to have the same ID...
Is JavaScript hard to learn?
Apr 03, 2025 am 12:20 AM
Learning JavaScript is not difficult, but it is challenging. 1) Understand basic concepts such as variables, data types, functions, etc. 2) Master asynchronous programming and implement it through event loops. 3) Use DOM operations and Promise to handle asynchronous requests. 4) Avoid common mistakes and use debugging techniques. 5) Optimize performance and follow best practices.
How to achieve parallax scrolling and element animation effects, like Shiseido's official website?
or:
How can we achieve the animation effect accompanied by page scrolling like Shiseido's official website?
Apr 04, 2025 pm 05:36 PM
Discussion on the realization of parallax scrolling and element animation effects in this article will explore how to achieve similar to Shiseido official website (https://www.shiseido.co.jp/sb/wonderland/)...
The difference in console.log output result: Why are the two calls different?
Apr 04, 2025 pm 05:12 PM
In-depth discussion of the root causes of the difference in console.log output. This article will analyze the differences in the output results of console.log function in a piece of code and explain the reasons behind it. �...
How to implement panel drag and drop adjustment function similar to VSCode in front-end development?
Apr 04, 2025 pm 02:06 PM
Explore the implementation of panel drag and drop adjustment function similar to VSCode in the front-end. In front-end development, how to implement VSCode similar to VSCode...
