从文件中一样一行的读取文件

read_line_from_file.go

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)
    }
}

read_line_to_string.go

package main

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

func ReadLine(filename string) {
    f, err := os.Open(filename)
    if err != nil {
        fmt.Println(err)
        return
    }
    defer f.Close()
    r := bufio.NewReaderSize(f, 4*1024)
    line, isPrefix, err := r.ReadLine()
    for err == nil && !isPrefix {
        s := string(line)
        fmt.Println(s)
        line, isPrefix, err = r.ReadLine()
    }
    if isPrefix {
        fmt.Println("buffer size to small")
        return
    }
    if err != io.EOF {
        fmt.Println(err)
        return
    }
}

func ReadString(filename string) {
    f, err := os.Open(filename)
    if err != nil {
        fmt.Println(err)
        return
    }
    defer f.Close()
    r := bufio.NewReader(f)
    line, err := r.ReadString('\n')
    for err == nil {
        fmt.Print(line)
        line, err = r.ReadString('\n')
    }
    if err != io.EOF {
        fmt.Println(err)
        return
    }
}

func main() {
    filename := `testfile`
    ReadLine(filename)
    ReadString(filename)
}