1 package main
2
3 import (
4 "bufio"
5 "fmt"
6 "os"
7 )
8
9 func main() {
10 /*
11 bufio:高效io读写
12 buffer缓存
13 io：input/output
14
15 将io包下的Reader，Write对象进行包装，带缓存的包装，提高读写的效率
16
17 func (b *Writer) Write(p []byte) (nn int, err error)
18 func (b *Writer) WriteByte(c byte) error
19 func (b *Writer) WriteRune(r rune) (size int, err error)
20 func (b *Writer) WriteString(s string) (int, error)
21
22 */
23
24 fileName := "D:\\Go\\web2\\aa.txt"
25 file, err := os.OpenFile(fileName, os.O_CREATE|os.O_WRONLY, os.ModePerm)
26 if err != nil {
27 fmt.Println(err)
28 return
29 }
30 defer file.Close()
31
32 w1 := bufio.NewWriter(file)
33 // n, err := w1.WriteString("helloworld")
34 // fmt.Println(err)
35 // fmt.Println(n) // 10
36 // w1.Flush() // 刷新缓冲区，即把缓冲区的数据写到文件
37
38 for i := 1; i <= 1000; i++ {
39 w1.WriteString(fmt.Sprintf("%d:hello", i))
40 }
41 w1.Flush() // 缓冲区还有数据
42 }
