Node.Js on windows - How to clear console

Question

Being totally new into node.js environment and philosophy i would like answers to few questions. I had downloaded the node.js for windows installer and also node package man

Answer 1

In my case I did it to loop for ever and show in the console a number ever in a single line:

class Status {

  private numberOfMessagesInTheQueue: number;
  private queueName: string;

  public constructor() {
    this.queueName = "Test Queue";
    this.numberOfMessagesInTheQueue = 0;
    this.main();
  }

  private async main(): Promise<any> {    
    while(true) {
      this.numberOfMessagesInTheQueue++;
      await new Promise((resolve) => {
        setTimeout(_ => resolve(this.showResults(this.numberOfMessagesInTheQueue)), 1500);
      });
    }
  }

  private showResults(numberOfMessagesInTheQuee: number): void {
    console.clear();
    console.log(`Number of messages in the queue ${this.queueName}: ${numberOfMessagesInTheQuee}.`)
  }
}

export default new Status();

When you run this code you will see the same message "Number of messages in the queue Test Queue: 1." and the number changing (1..2..3, etc).

Answer 2

You can use the readline module:

readline.cursorTo(process.stdout, 0, 0) moves the cursor to (0, 0).

readline.clearLine(process.stdout, 0) clears the current line.

readline.clearScreenDown(process.stdout) clears everything below the cursor.

const READLINE = require('readline');

function clear() {
    READLINE.cursorTo(process.stdout, 0, 0);
    READLINE.clearLine(process.stdout, 0);
    READLINE.clearScreenDown(process.stdout);
}

Answer 3

Based on sanatgersappa's answer and some other info I found, here's what I've come up with:

function clear() {
    var stdout = "";

    if (process.platform.indexOf("win") != 0) {
        stdout += "\033[2J";
    } else {
        var lines = process.stdout.getWindowSize()[1];

        for (var i=0; i<lines; i++) {
            stdout += "\r\n";
        }
    }

    // Reset cursur
    stdout += "\033[0f";

    process.stdout.write(stdout);
}

To make things easier, I've released this as an npm package called cli-clear.

Answer 4

On mac, I simply use Cmd + K to clear the console, very handy and better than adding codes inside your project to do it.

Answer 5

Belated, but ctrl+l works in windows if you're using powershell :) Powershell + chocolatey + node + npm = winning.

Answer 6

Ctrl + L This is the best, simplest and most effective option.