示例代码

// File_test2 project main.go
package main

import (
	"bufio"
	"fmt"
	"io"
	"os"
	"strings"
)

func ReadLine(fileName string,handler func(string)) error {
	f,err := os.Open(fileName)
	if err != nil {
		return err
	}
	buf := bufio.NewReader(f)
	for {
		line,err := buf.ReadString('\n')
		line = strings.TrimSpace(line)
		handler(line)
		if err != nil {
			if err == io.EOF {
				return nil
			}
			return err
		}
	}
	return nil
}

func Print(line string) {
	fmt.Println(line)
}

func main() {
	ReadLine("test.txt",Print)
}

测试样例

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