有关peek在实际应用中的疑问

请问在这一串代码中resp.body为什么会从第1025个字符开始读取 但是bodyReader就没事呢,感觉resp.body也没被处理呀 `````` package fetcher import ( "bufio" "fmt" "golang.org/x/net/html/charset" "golang.org/x/text/encoding" "golang.org/x/text/encoding/unicode" "golang.org/x/text/transform" "io/ioutil" "log" "net/http" ) const url = "http://www.zhenai.com/zhenghun" func Fetch(url string) ([]byte, error) { resp, err := http.Get(url) if err != nil { return nil, err } defer resp.Body.Close() if resp.StatusCode != http.StatusOK { return nil, fmt.Errorf("wrong status code: %d", resp.StatusCode) } bodyReader := bufio.NewReader(resp.Body) e := determinEncoding(bodyReader) utf8Reader := transform.NewReader(resp.Body, e.NewDecoder()) // !!!!!问题出在这里 return ioutil.ReadAll(utf8Reader) } func determinEncoding( r *bufio.Reader) encoding.Encoding { bytes, err := r.Peek(1024) if err != nil { log.Printf("Fetcher error: %v", err) return unicode.UTF8 } e, _, _ := charset.DetermineEncoding(bytes, "") return e } ``````