typescript - Visual Studio Code compile on save

Question

How can I configure Visual Studio Code to compile typescript files on save?

I see it is possible to configure a task to build the file in focus using the ${file} as an argument. But I would like this to be done when a file is saved.

Answer 1

May 2018 update:

As of May 2018 you no longer need to create tsconfig.json manually or configure task runner.

1. Run tsc --init in your project folder to create tsconfig.json file (if you don't have one already).
2. Press Ctrl+Shift+B to open a list of tasks in VS Code and select tsc: watch - tsconfig.json.
3. Done! Your project is recompiled on every file save.

You can have several tsconfig.json files in your workspace and run multiple compilations at once if you want (e.g. frontend and backend separately).

Original answer:

You can do this with Build commands:

Create a simple tsconfig.json with "watch": true (this will instruct compiler to watch all compiled files):

{
    "compilerOptions": {
        "target": "es5",
        "out": "js/script.js",
        "watch": true
    }
}

Note that files array is omitted, by default all *.ts files in all subdirectories will be compiled. You can provide any other parameters or change target/out, just make sure that watch is set to true.

Configure your task (Ctrl+Shift+P -> Configure Task Runner):

{
    "version": "0.1.0",
    "command": "tsc",
    "showOutput": "silent",
    "isShellCommand": true,
    "problemMatcher": "$tsc"
}

Now press Ctrl+Shift+B to build the project. You will see compiler output in the output window (Ctrl+Shift+U).

The compiler will compile files automatically when saved. To stop the compilation, press Ctrl+P -> > Tasks: Terminate Running Task

I've created a project template specifically for this answer: typescript-node-basic