io/ioutil

读取文件写入文件

  1. package main
  3. import (
  4.     "fmt"
  5.     "io/ioutil"
  6.     "os"
  7. )
  9. func main() {
  10.     inputFile := "nginx.conf"
  11.     outputFile := "abc.txt"
  12.     buf, err := ioutil.ReadFile(inputFile)
  13.     if err != nil {
  14.         fmt.Fprintf(os.Stderr, "File Error: %s\n", err)
  15.     }
  16.     fmt.Printf("%s\n", string(buf))
  17.     err = ioutil.WriteFile(outputFile, buf, 0644)
  18.     if err != nil {
  19.         panic(err.Error())
  20.     }
  21. }

io.Copy

复制文件

  1. package main
  3. import (
  4.     "fmt"
  5.     "io"
  6.     "os"
  7. )
  9. func CopyFile(dstName, srcName string) (written int64, err error) {
  10.     src, err := os.Open(srcName)
  11.     if err != nil {
  12.         fmt.Println(err)
  13.         return
  14.     }
  15.     defer src.Close()
  16.     dst, err := os.OpenFile(dstName, os.O_WRONLY|os.O_CREATE, 0644)
  17.     if err != nil {
  18.         fmt.Println(err)
  19.         return
  20.     }
  21.     defer dst.Close()
  23.     return io.Copy(dst, src)
  24. }
  26. func main() {
  27.     CopyFile("abc2.txt", "abc.txt")
  28.     fmt.Println("Copy done!")
  29. }