[javascript] Is there a way to create and run javascript in Chrome?

Is there a way, like an extension or application, in Chrome to create and run .js files in Chrome?

You don't necessarily need to have an HTML page. Open Chrome, press Ctrl+Shift+j and it opens the JavaScript console where you can write and test your code.

- Chrome JavaScript Console

You should write in file:

<script>
     //write your JavaScript code here
</script>

save it with .html extension and open with browser.

For example:

// this is test.html
<script>
   alert("Hello");
   var a = 5;
   function incr(arg){
       arg++;
       return arg;
   }       
   alert(a);
</script>

Try this:
1. Install Node.js from https://nodejs.org/
2. Place your JavaScript code into a .js file (e.g. someCode.js)
3. Open a cmd shell (or Terminal on Mac) and use Node's Read-Eval-Print-Loop (REPL) to execute someCode.js like this:
> node someCode.js

Hope this helps!

You can also open your js file path in the chrome browser which will only display text.

However you can dynamically create the page by including:

var script = document.createElement('script');
script.type = 'text/javascript';
script.src = 'myjs.js';
document.head.appendChild(script);

Now you can have access to the js variables and functions in the console.

Now when you explore the elements it should have included.

So not i guess you dont need a html file.

Open a basic text editor and type out your html. Save it as .html If you type in file:///C:/ into the address bar you can then navigate to your chosen file and run it. If you want to open a file that is on a server type in file:/// and instead of C:/ the first letter of the server followed by :/.

Usually one uses text editor to create source files (like JavaScript). I use VisualStudio which have intellisence supprt for JavaScript, but any other editor will do (vim or notepad on Windows are both fine).

To run JavaScript by itself you need something that can do that. I.e. on Windows you can directly run script from console using CScript script.js command. There are other ways to run JavaScript on Windows and other OS.

Browsers (like Chrome) do not run JavaScript by itself, only as part of a page or extensions. It is unclear what one would expect of browser to do with JavaScript by itself.

You need an HTML page to load a JS file.

How to create a Javascript Bookmark in Chrome:

You can use a Javascript bookmark: https://helloacm.com/how-to-write-chrome-bookmark-scripts-step-by-step-tutorial-with-a-steemit-example/. Just create a bookmark to look like this:

Ex:

Name:

Test javascript bookmark in Chrome

URL:

javascript:alert('Hello world!');

Just precede the URL with javascript:, followed by your Javascript code. No space after the colon is required.

Here's how it looks as I'm typing it in:

Now save and then click on your newly-created Javascript bookmark, and you'll see this:

You can do multi-line scripts too. If you include any comments, however, be sure to use the C-style multi-line comments ONLY (/* comment */), and NOT the C++-style single-line comments (// comment), as they will interfere. Here's an example:

URL:

javascript:

/* This is my javascript demo */

function multiply(a, b) 
{
    return a * b;
}

var a = 1.4108;
var b = 3.7654;
var result = multiply(a, b);
alert('The result of ' + a + ' x ' + b + ' = ' + result.toFixed(4));

And here's what it looks like as you edit the bookmark, after copying and pasting the above multi-line script into the URL field for the bookmark:

.

And here's the output when you click on it:

References:

1. https://superuser.com/questions/192437/case-sensitive-searches-in-google-chrome/582280#582280
2. https://gist.github.com/borisdiakur/9f9d751b4c9cf5acafa2
3. Google search for "chrome javascript() in bookmark"
4. https://helloacm.com/how-to-write-chrome-bookmark-scripts-step-by-step-tutorial-with-a-steemit-example/
5. https://helloacm.com/how-to-write-chrome-bookmark-scripts-step-by-step-tutorial-with-a-steemit-example/
6. https://javascript.info/hello-world
7. JavaScript equivalent to printf/String.Format