复制方法一：
func copyFile1(srcFile,destFile string)(int,error){
file1,err:=os.Open(srcFile)
if err != nil{
return 0,err
}
file2,err:=os.OpenFile(destFile,os.O_WRONLY|os.O_CREATE,os.ModePerm)
if err !=nil{
return 0,err
}
defer file1.Close()
defer file2.Close()
//拷贝数据
bs := make([]byte,1024,1024)
n :=-1//读取的数据量
total := 0
for {
n,err = file1.Read(bs)
if err == io.EOF || n == 0{
fmt.Println("拷贝完毕。。")
break
}else if err !=nil{
fmt.Println("报错了。。。")
return total,err
}
total += n
file2.Write(bs[:n])
}
return total,nil
}
复制方法二
func copyFile2(srcFile, destFile string)(int64,error){
file1,err:=os.Open(srcFile)
if err != nil{
return 0,err
}
file2,err:=os.OpenFile(destFile,os.O_WRONLY|os.O_CREATE,os.ModePerm)
if err !=nil{
return 0,err
}
defer file1.Close()
defer file2.Close()
return io.Copy(file2,file1)
}
复制方法三L:
func copyFile3(srcFile, destFile string)(int,error){
input, err := ioutil.ReadFile(srcFile)
if err != nil {
fmt.Println(err)
return 0,err
}
err = ioutil.WriteFile(destFile, input, 0644)
if err != nil {
fmt.Println("操作失败：", destFile)
fmt.Println(err)
return 0,err
}
return len(input),nil
}
文件断点续传：
package main
import (
"strings"
"fmt"
"log"
"os"
"io"
"strconv"
)
func main() {
srcFile :="D:\\BaiduNetdiskDownload\\2019Golang进阶实战编程(学完基础必看)【千锋GO语言】\\2019版-千锋golang进阶-课件\\第08节_复制文件\\第8节_复制文件.md"
s := srcFile[strings.LastIndex(srcFile,"\\")+1:]
fmt.Println(s)
tempFile :=s +"temp.md"
fmt.Println(tempFile)
//获取目标文件得file
file, e := os.Open(srcFile)
handle1(e)
//获取输出文件得file
openFile, e := os.OpenFile(s, os.O_WRONLY|os.O_CREATE, os.ModePerm)
handle1(e)
//获取临时文件得file
file2, e := os.OpenFile(tempFile, os.O_CREATE|os.O_RDWR, os.ModePerm)
handle1(e)
defer file.Close()
defer file2.Close()
defer openFile.Close()
// 读取临时文件的内容，设置从哪里开始
// seek 方法，设置偏移量，后面参数距离开始，还是结束，还是当前文职
file2.Seek(0,io.SeekStart)
//设置读的字节数
bs := make([]byte, 100, 100)
//这个地方不需要处理异常
n, err := file2.Read(bs)
/*if err != nil{
fmt.Println(err)
}*/
fmt.Println(n)
countstr := string(bs[:n])
fmt.Println(countstr)
// 讲字符串转哈伟int类型去接受
i, _ := strconv.ParseInt(countstr, 10, 64)
fmt.Println(i)
file.Seek(i,0)
openFile.Seek(i,0)
bytes := make([]byte, 1024, 1024)
n1 :=-1
n2 :=-1
total :=int(i)
for{
n1, err = file.Read(bytes)
if n1 ==0||err==io.EOF{
fmt.Println("文件赋值完毕")
file2.Close()
os.Remove(tempFile)
fmt.Println(total)
break
}
n2, _ = openFile.Write(bytes[:n1])
total +=n2
file2.Seek(0,io.SeekCurrent)
file2.WriteString(strconv.Itoa(n2))
/*if total>800{
panic("zhongduan")
}*/
}
}
func handle1(e error) {
if e !=nil {
log.Fatal(e)
}
}