Develop Reference

How do you get an HTML element ID to autocomplete in VSCode JavaScript?

I'm trying to get intellisense to work with JavaScript in VSCode, but when I try to reference an HTML file in the project it doesn't recognize IDs.
In the picture you can see the same project works fine in Visual Studio.
Is there a way to get this functionality in VSCode?

Sadly, Visual Studio and VS Code are two completely different software's. Visual Studio is an IDE (Integrated Development Environment), this means it has more features than a normal text editor (for example VS Code or Atom). VS Code is a text editor, however you can install extensions to make it more into an IDE.
The best solution is to look at VS Codes market place and try and find an extension that will auto complete the HTML tags. I personally haven't found any extension for it.
Hope this helps, if you need any more advice or help DM me on discord CallumS005#9458 and I'll be happy to try and help.

Run isolated JavaScript commands in VS Code (not current file)

I am looking for a way to run individual commands in VS Code but not the whole file. I do work on client websites where a lot of my code will not run in a standard debugger or in the Quokka extension because it relies on the page that I am working on (and running in the debugger does not perfectly emulate how my code will run. But sometimes I like to run a few lines of code or a single function separately to make sure I have it set right without having to copy my code over to the online platform used to execute it and load up a preview link. Normally what I like to do is open a new chrome tab at about:blank and use the dev console there to paste in my code and this is my "playground" of sorts. Is there any form of active JS engine that I can do this in without having to save these lines to a new file and run the debugger?

If you looking all these things in VS code I think it will be a bit hard because of this.
to run JS code snippet VS code must have JS engine like same for PHP its compiler or same for any other language and adding these compilers in IED will again make these IEDs fat and CPU costly.
BUT Still, you can do one thing if you have a node js installed open Terminal outside or inside the VS code.
and type
$node
This will open a JS playground. Where you can execute js code snippets
but here you will not be able to access DOM, WINDOW object, etc.
In case you found any plugin which executes js code in VS CODE with DOM, window please let me know.

Auto-format javascript code in RStudio Server

In RStudio it´s possible to autoformat R Code with CTRL+SHIFT+A (e.g. see this answer). Now my question is, how to autoformat javascript code in RStudio (e.g. if you are working on a shiny app).

The prettifyAddins package I've just made provides two RStudio addins for JavaScript files and more: an addin which only reindents the code and an addin which prettifies the code, e.g. it adds semi-colons when they are missing. I will submit it to CRAN soon.
Update
I updated prettifyAddins. It has now addins using the V8 package, and Shiny is not used for these addins, the prettified code directly replaces the current code.
Another possibility is my (freshly built) package aceEditor. It opens the Ace editor in the viewer pane of RStudio:
This provides a second source editor in RStudio. And many languages are supported.

Adding JQuery/Javascript Files to Project

I have a project I am working on at work that is ASP.NET in TFS. I have checked out the solution and have made some adjustments to the code behind with no issues. When I try to add JQuery and a Javascript file to the project, it does it fine in Visual Studio 2012. But when rebuilding and running it won't execute the javascript code. It's like it ignores it. When I put breakpoints in the Javascript file I get the message 'The breakpoint will not currently be hit, no symbols have been loaded for this document'. I simply cannot get the web page to acknowlegde either the JS file, or the JQuery file.
(And yes, I have scoured StackOverflow.com and tried all the suggestions mentioned)
Any suggestions appreciated!

Which program to use when running javascript code made in notepad

Ok, recently I started doing some tutorials in javascript. Soon I had finished doing some coding on notepad, saved it as " .js" but when I tried to open it I could not find a suitable program, hopefully, soomeone can tell me a method of running the code.
The first thing I did was try and download java, but quit the installer after seeing the ad based installer including vosteran, a web browser hijacker which I have had some experience with. Finally, is it necessary to download notepad ++ for this?
Thanks

It seems that you don't have a clear understanding of JavaScript and how it interacts with HTML. Java and JavaScript are two complete differently languages.
.js files are usually linked within a .html file or some server side language file, i.e. .php, .aspx. And the HTML file is opened with your browser, for example, Internet Explorer, Google Chrome or Firefox.
You should include the .js file in your HTML file using:
<script src="yourscript.js"></script>
Within the HTML file you can then invoke the methods and use the variables declared in your custom .js file.

You run js files in a webbrowser. Include files between tags.
Example:

There are two main options of running Javascript
1 In the browser
2 Or as a process
Choosing which one depends on your code. Please post an example of a what you are working on.
If your code fits option 1, then you will just need a small HTML file that includes reference to your javascript file.
If your code is not meant for a browser, you will likely need to install Nodejs. This is a CommonJS implementation of server-side js.
A note on Java and Javascript. They are in no way related. Netscape licensed the name from makers of Java and renamed language to Javascript in hopes it would inherate some of Java's popularity.