在 Javascript 中暂停

Question

Is there a way to pause code execution in JS? I'm trying to create a browser based terminal, and I'm having trouble creating a user input type functionality.

Essentially I want to have a parameter called currentCommand which initializes in a false state and a function which waits for the currentCommand variable to change before completing like:

 while(;currentCommand) { pass; }

Here's how I'd like it to be applied:

 let currentCommand = false; // this variable holds the command the user has entered // Placeholder of a user text input document.addEventListener('keydown', () => { currentCommand = 'Timmy'; } // Problematic function function getAnswer(){ currentCommand = false; // something that will pause the function while currentCommand is false return currentCommand } // Example of implementation console.log('Hi what is your name?'); let answer = getAnswer(); console.log(`${asnwer}, that's a silly name`);

An example implementation for context: https://jsfiddle.net/u98r1dyp/17/#&togetherjs=jmnaRa89uT

Answer 1

The closest you can probably get would be to promisify whichever API you're using and await its resolution:

 const getAnswer = () => new Promise((resolve) => { document.addEventListener('keydown', () => { resolve('Timmy'); }); }); (async () => { console.log('Hi what is your name?'); const answer = await getAnswer(); console.log(`${answer}, that's a silly name`); })();

(also note that you need another ) at the end of addEventListener , and you probably want to spell answer right - asnwer is never defined)