app.js:
12345678910111213141516171819202122 | 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');} |
123456789101112131415161718192021222324252627282930313233343536373839404142 | console.log('start nodes.js');const fs = require('fs');var addNote = (title,body)=>{ var notes = []; var note = { title, body }; try{ //读取json文件，读出来是string var notesString = fs.readFileSync('notes-data.json'); // string转换为json对象 notes = JSON.parse(notesString); }catch(e){ } //增加 notes.push(note); //保存 fs.writeFileSync('notes-data.json',JSON.stringify(notes));}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}; |
打开控制台，在当前目录下输入：
1 | > node app.js add --title="buy book2" --body="jonson" |
将节点添加到notes-data.json文件中.
再次输入：
1 | > node app.js add --title="buy book2" --body="jonson" |
notes-data.json:
1 | [{"title":"buy book2","body":"jonson"},{"title":"buy book2","body":"jonson"}] |
12345678910111213141516171819202122232425262728293031323334353637383940414243444546 | console.log('start nodes.js');const fs = require('fs');var addNote = (title,body)=>{ var notes = []; var note = { title, body }; try{ var notesString = fs.readFileSync('notes-data.json'); notes = JSON.parse(notesString); }catch(e){ } //筛选出相同的节点 var duplicateNotes = notes.filter((note)=>note.title===title); //没有相同的节点 if(duplicateNotes.length ===0){ notes.push(note); fs.writeFileSync('notes-data.json',JSON.stringify(notes)); }}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}; |
再次输入不会添加节点：
1 | > node app.js add --title="buy book2" --body="jonson" |
本文链接： https://dreamerjonson.com/2018/11/13/node-9/
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