~~~ package main import ( "io" "strings" "os" "fmt" ) func ExampleCopy() { dst := os.Stdout src := strings.NewReader("Hello World") if _, err := io.Copy(dst, src); err == nil { fmt.Println(err) } } func ExampleCopyBuffer() { dst := os.Stdout src := strings.NewReader("Hello World") buf := make([]byte, 8) if _, err := io.CopyBuffer(dst, src, buf); err != nil { fmt.Println(err) } } func ExampleCopyN() { dst := os.Stdout src := strings.NewReader("Hello 世界") n := int64(9) if _, err := io.CopyN(dst, src, n); err != nil { fmt.Println(err) } } func ExampleReaAtLeast() { r := strings.NewReader("Hello World") buf := make([]byte, 8) min := 5 if _, err := io.ReadAtLeast(r, buf, min); err != nil { fmt.Println(err) } fmt.Println("buf :", string(buf)) } func ExampleReadFull() { r := strings.NewReader("Hello World") buf := make([]byte, 18) if _, err := io.ReadFull(r, buf); err != nil { fmt.Println(err) } fmt.Println(string(buf)) } func ExampleWriteString() { w := os.Stdout s := "Hello World" if _, err := io.WriteString(w, s); err != nil { fmt.Println(err) } } func main() { //TODO : io.Copy(dst, src) - 将副本从 src 复制到 dst //ExampleCopy() //TODO : io.CopyBuffer(dst, src, buf) - 将副本从 src 复制到 dst(带缓冲) //ExampleCopyBuffer() //TODO : io.CopyN(dst, src, n) - 将副本从 src 复制到 dst(复制n个字节) //ExampleCopyN() //TODO : io.ReadAtLeast(r, buf, min) - 从r中读取min个字节到buf中 //ExampleReaAtLeast() //TODO : io.ReadFull(r, buf) - 从r中读取到buf,直至buf填满(r读完时, buf未填满会报 io.ErrUnexpectedEOF) //ExampleReadFull() //TODO : io.WriteString(w, s) - 将s的内容写入w //ExampleWriteString() //待续... var dst io.Writer = os.Stdout w, ok := dst.(io.Writer) fmt.Println(dst) fmt.Println(&dst) fmt.Println(w, ok) fmt.Println(&w, ok) } ~~~