how to run a js method from command line code example

Example 1: run command line using javascript

const { exec } = require("child_process");

exec("ls -la", (error, stdout, stderr) => {
    if (error) {
        console.log(`error: ${error.message}`);
        return;
    }
    if (stderr) {
        console.log(`stderr: ${stderr}`);
        return;
    }
    console.log(`stdout: ${stdout}`);
});

Example 2: how to run js script

$ node // now we can execute code in console
> 2 + 4 //our input
6 //output 
> .exit // or ctrl + c