Question

我的服务器中有一个非常简单的http响应，其中我对json编码结构。但它只发送{}

的空白

我不知道我做错了但是没有错误。这是我的json编码：

    // Set uuid as string to user struct
    user := User{uuid: uuid.String()}
    fmt.Println(user) // check it has the uuid

    responseWriter.Header().Set("Content-Type", "application/json")
    responseWriter.WriteHeader(http.StatusCreated)

    json.NewEncoder(responseWriter).Encode(user)

在接收端，数据有：

Content-Type application/json
Content-Length 3
STATUS HTTP/1.1 201 Created
{}

为什么不给我uuid数据？我的编码有问题吗？

Answer 1

通过the first character of the identifier's name a Unicode upper case letter (Unicode class "Lu")导出字段名称。

试试这个：

package main

import (
    "encoding/json"
    "fmt"
    "log"
    "net/http"
)

type User struct {
    Uuid string
}

func handler(responseWriter http.ResponseWriter, r *http.Request) {
    user := User{Uuid: "id1234657..."} // Set uuid as string to user struct
    fmt.Println(user)                 // check it has the uuid
    responseWriter.Header().Set("Content-Type", "application/json")
    responseWriter.WriteHeader(http.StatusCreated)
    json.NewEncoder(responseWriter).Encode(user)
}

func main() {
    http.HandleFunc("/", handler)            // set router
    err := http.ListenAndServe(":9090", nil) // set listen port
    if err != nil {
        log.Fatal("ListenAndServe: ", err)
    }
}

输出（http://localhost:9090/）：

{"Uuid":"id1234657..."}

JSON编码返回空白Golang

1 个答案: