node中的读取流createReadStream、写入流createWriteStream和管道流pipe

# 读取流createReadStream

const fs = require('fs')
 
let readStream = fs.createReadStream('./data/input.txt');
 
let count = 0;
let str = ""
readStream.on('data', data => {
    str += data;
    count++
})
 
readStream.on('end', () => {
    console.log("count:", count)
    console.log("str:", str)
})
 
readStream.on('error', err => {
    console.log(err)
})

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# 写入流createWriteStream

const fs = require('fs')
 
let str = ""
for (let i = 0; i < 500; i++){
    str+='这是写入流输出的数据\n'
}
 
let writeStream = fs.createWriteStream('./data/output.txt');
 
writeStream.write(str)
 
writeStream.end();//只有添上这句代码，下面的finish事件才能被监听
 
writeStream.on('finish', () => {
    console.log('写入完成')
})

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# 管道流pipe

const fs = require('fs')
 
let readStream = fs.createReadStream('./data/input.txt');
let writeStream = fs.createWriteStream('./data/output.txt');
 
//读取input.txt文件内容，并将内容写入到output.txt文件中(原内容会被替换)
readStream.pipe(writeStream)
 
console.log('程序执行完毕')

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#NodeJs

上次更新: 2024/01/30, 00:35:17

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