golang readline

In Go 1.1 and newer the most simple way to do this is with a bufio.Scanner. Here is a simple example that reads lines from a file:

从Go 1.1开始，最新也是最简洁的方法就是用bufio.Scanner, 下面的例子将展示逐行读取

package main

import (
    "bufio"
    "fmt"
    "log"
    "os"
)

func main() {
    file, err := os.Open("/path/to/file.txt")
    if err != nil {
        log.Fatal(err)
    }
    defer file.Close()

    scanner := bufio.NewScanner(file)
    for scanner.Scan() {
        fmt.Println(scanner.Text())
    }

    if err := scanner.Err(); err != nil {
        log.Fatal(err)
    }
}

This is the cleanest way to read from a Reader line by line.

这是最好的方式从Reader中逐行读取

There is one caveat: Scanner will error with lines longer than 65536 characters. If you know your line length is greater than 64K, use the Buffer() method to increase the scanner’s capacity:

警告：如果单行超过 65536 个字符，那么Scanner就会出问题。 如果你单行超过 65536 个字符， 你应该重写Reader.Read()

参考： https://stackoverflow.com/questions/8757389/reading-a-file-line-by-line-in-go#16615559#753

当单行字节超过65535个字节（也就是64k）的时候，请使用Buffer()方法来增加scanner的容量

scanner := bufio.NewScanner(file)

const maxCapacity = longLineLen  // your required line length
buf := make([]byte, maxCapacity)
scanner.Buffer(buf, maxCapacity)

for scanner.Scan() {}