In the background operation, the operation will certainly file stream, nodeJs file operations --- FS
A: introduction
let fs = require('fs')
Second, read the contents of the file --- readFile
1, create a file: a.text file contents: bbb
2 reads
fs.readFile('./a.text',(err,data)=> { if (err) { throw err console.log(err) } else { console.log(data.toString()) } })
3, content presentation
Third, write to the file contents --- writeFile
1, write to
/ **
* write
* the file path
* written content
* whether to overwrite (if not write it overwrites the original content)
* callback
* * /
fs.writeFile('./b.text','bbb',{flag: 'a'}, (err) => { if (err) { throw err } else { console.log('写入成功') } })
Note: If it does not, the system will default to you to create this file
2, view results
Fourth, the synchronous read --- readFileSync (file path)
let data = fs.readFileSync('./b.text')
Fifth, the synchronous write --- writeFileSync (file path, write content, flag)
let data = fs.writeFileSync('./b.text','cccc',{flag: 'a'})