> npm install --save yargs

const yargs = require('yargs');
console.log('Start app.');

console.log(process.argv);

console.log('yargs',yargs.argv);

var command = process.argv[2];

> node app.js remove --title="buy book"

Start app.
[ '/Users/jackson/.nvm/versions/node/v10.13.0/bin/node',
  '/Users/jackson/Desktop/compaign/app.js',
  'remove',
  '--title=buy book' ]
yargs { _: [ 'remove' ], title: 'buy book', '$0': 'app.js' }
Remove node

//打印字符串
const yargs = require('yargs');
const nodes = require('./nodes.js')
console.log('Start app.');

console.log(process.argv);

console.log('yargs',yargs.argv);
const argv = yargs.argv;
var command = process.argv[2];

if(command==='add'){
  nodes.addNote(argv.title,argv.body);
}else if(command === 'list'){
  nodes.getAll();

}else if(command =='read'){
  nodes.getNote(argv.title);
}else if(command=='remove'){
  nodes.removeNote(argv.title);
}else{
  console.log('command not find');
}

console.log('start nodes.js');

var addNote = (title,body)=>{
console.log('Adding note',title,body);
}

var getAll = ()=>{
console.log('Get All notes');
};

var getNote = (title)=>{

  console.log('getting note',title);
};

var removeNote = (title)=>{
  console.log('Removing note',title);
};

module.exports = {
    addNote,
    getAll,
    getNote,
    removeNote
};

> node app.js remove --title="buy book"

start nodes.js
Start app.
[ '/Users/jackson/.nvm/versions/node/v10.13.0/bin/node',
  '/Users/jackson/Desktop/compaign/app.js',
  'remove',
  '--title=buy book' ]
yargs { _: [ 'remove' ], title: 'buy book', '$0': 'app.js' }
Removing note buy book

> node app.js add --title="buy book" --body="jonson"

start nodes.js
Start app.
[ '/Users/jackson/.nvm/versions/node/v10.13.0/bin/node',
  '/Users/jackson/Desktop/compaign/app.js',
  'add',
  '--title=buy book',
  '--body=jonson' ]
yargs { _: [ 'add' ],
  title: 'buy book',
  body: 'jonson',
  '$0': 'app.js' }
Adding note buy book jonson