Golang 拷贝文件操作

代码案例：

package main

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

func main() {
	srcFile := "./test1.txt"
	dstFile := "./abc.txt"
	_, err := CopyFile(dstFile, srcFile)
	if err == nil {
		fmt.Println("拷贝完成")
	} else {
		fmt.Println("拷贝失败 err=%v", err)
	}
}

func CopyFile(dstFileName string, srcFileName string) (written int64, err error) {
	//打开srcFileName
	srcFile, err := os.Open(srcFileName)
	if err != nil {
		fmt.Println("open file err=%v\n", err)
	}
	//通过srcFile，获取到Reader
	reader := bufio.NewReader(srcFile)
	defer srcFile.Close()
	//打开dstFileName
	dstFile, err := os.OpenFile(dstFileName, os.O_WRONLY|os.O_CREATE, 0666)
	if err != nil {
		fmt.Println("open file err=%v\n", err)
	}
	//通过distFile，获取到Writer
	writer := bufio.NewWriter(dstFile)
	defer dstFile.Close()
	return io.Copy(writer, reader)
}