go讀取檔案內容寫入另一檔案中

package main

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

func main(){
    readAndWrite()
}

func readAndWrite(){
    //讀取檔案
    f := "C:\\Users\\Administrator\\Desktop\\go\\1.txt"
    file, _ := os.Open(f)
    defer file.Close()
    var buf [128]byte // 記錄一次讀取的量
    var content []byte // 整體的資料量
 

    for {
        n, err := file.Read(buf[:]) // 根據
        if err == io.EOF {
            // 讀取結束
            fmt.Println("read end")
            break
        }
        if err != nil {
            fmt.Println("read file err ", err)
            return
        }
        content = append(content, buf[:n]...)
    }
    
 
//fmt.Println(string(content))
    //寫入檔案
    writeFile := "C:\\Users\\Administrator\\Desktop\\go\\write.txt"
    fileto, _ := os.OpenFile(writeFile, os.O_WRONLY, 0666)
    defer fileto.Close()
    res,error :=fileto.WriteString(string(content))
    if error != nil {
        fmt.Println("write file err ", error)
        
 
return
    }
    if res == 1002 {
        fmt.Println("write success")
        return 
    }
}