utf-8中的错误解码字符串中的JSON解码器

Question

I have a problem with json decoder in Go. I have client (dotnet core) and server (go) which are communicate via sockets. Encoding is setted to utf-8. After decoding on server side is not one of string in correct format.

Go decoding code:

buf := make([]byte, bufferSize)
_, err := conn.Read(buf)
if err != nil {
    fmt.Println("Error reading:", err.Error())
}

s := string(buf[:])
r := strings.NewReader(s)
d := json.NewDecoder(r)

request := Request{}
d.Decode(&request)

Variable s contains correct string before decoding: https://i.stack.imgur.com/EUYF3.png and args contains correct word "zářit".

After decoding is string broken and contains this: https://i.stack.imgur.com/Zqan8.png

I don't understand representation ...+2 more from second image and I don't know how to decode this string correct way.

EDIT:

The core of the problem can be reproduced by this code:

package main

import (
    "fmt"
    "encoding/json"
    "strings"
)

type Request struct {
    Arg     string
}

func main() {
    s := "{\"Arg\": \"zářit\"}"
    r := strings.NewReader(s)
    d := json.NewDecoder(r)

    request := Request{}
    d.Decode(&request)

    for i := 0; i < len(request.Arg); i++ {
        char := request.Arg[i]
        fmt.Print(string(char))
    }
    fmt.Println()
    fmt.Println(request.Arg)
}

Why output is not the same? How I should get the same result?

Answer 1

main

import (
    "fmt"
    "encoding/json"
    "strings"
)

type Request struct {
    Arg     string
}

func main() {
    s := "{\"Arg\": \"zářit\"}"
    r := strings.NewReader(s)
    d := json.NewDecoder(r)


    request := Request{}
    d.Decode(&request)

    for i := 0; i < len(request.Arg); i++ {
        char := request.Arg[i]
        fmt.Print(string(char))
    }

    //example correct show
    var tmp []rune
    for _, x := range request.Arg {
        fmt.Printf("%x : %v : %c
", x,x,x)
        tmp = append(tmp, rune(x))
    }
    fmt.Printf("Result output: %v : `%s`
", tmp, string(tmp))


    fmt.Println()
    fmt.Println(request.Arg)

}

output

/usr/local/go/bin/go run /home/spouk/go/src/simple/translator

/error_json_code.go
záÅit7a : 122 : z
e1 : 225 : á
159 : 345 : ř
69 : 105 : i
74 : 116 : t
Result output: [122 225 345 105 116] : `zářit`

zářit

Process finished with exit code 0