这些包中的大多数都依赖于reflect包来实现这些功能。

fmt.Sprintf()正在使用-> func (p *pp) printArg(参数接口{}，动词符文)的标准库

转到第638行-> https://golang.org/src/fmt/print.go

反射:

https://golang.org/pkg/reflect/

示例代码:

https://github.com/donutloop/toolkit/blob/master/debugutil/prettysprint.go

我建议使用json.Unmarshal() 我试着打印id，希望它有帮助:

var jsonString = `{"Id": 1, "Title": "the title", "Name": "the name","Data": "the data","Commits" : "the commits"}`
var jsonData = []byte(jsonString)

var data Project

var err = json.Unmarshal(jsonData, &data)
if err != nil {
    fmt.Println(err.Error())
    return
}

fmt.Println("Id :", data.Id)

    type Response struct {
        UserId int    `json:"userId"`
        Id     int    `json:"id"`
        Title  string `json:"title"`
        Body   string `json:"body"`
    }

    func PostsGet() gin.HandlerFunc {
        return func(c *gin.Context) {
            xs, err := http.Get("https://jsonplaceholder.typicode.com/posts")
            if err != nil {
                log.Println("The HTTP request failed with error: ", err)
            }
            data, _ := ioutil.ReadAll(xs`enter code here`.Body)


            // this will print the struct in console            
            fmt.Println(string(data))


            // this is to send as response for the API
            bytes := []byte(string(data))
            var res []Response
            json.Unmarshal(bytes, &res)

            c.JSON(http.StatusOK, res)
        }
    }

您可以先执行json mashal并将其作为字符串打印。你可以看到整个struct的值。

package main

import "fmt"
import "json"

type Project struct {
    Id int64 `json:"project_id"`
    Title string `json:"title"`
    Name string `json:"name"`
}

func main() {
    o := Project{Id: 4, Name: "hello", Title: "world"}
    om, _ := json.marshal(o)
    log.Printf("%s\n", string(om))
}

访问这里查看完整的代码。在这里你还可以找到一个在线终端的链接，在那里可以运行完整的代码，程序表示如何提取结构的信息(字段的名称、类型和值)。下面是只打印字段名的程序片段。

package main

import "fmt"
import "reflect"

func main() {
    type Book struct {
        Id    int
        Name  string
        Title string
    }

    book := Book{1, "Let us C", "Enjoy programming with practice"}
    e := reflect.ValueOf(&book).Elem()

    for i := 0; i < e.NumField(); i++ {
        fieldName := e.Type().Field(i).Name
        fmt.Printf("%v\n", fieldName)
    }
}

/*
Id
Name
Title
*/

有时，将结构体打印为有效的Go代码(相当于Go /ast代码)可能会很方便。出于这个目的，https://github.com/hexops/valast做得很好:

package main

import (
    "fmt"

    "github.com/hexops/valast"
)

type ProjectData struct {
    Title   string `json:"title"`
    Name    string `json:"name"`
    Data    string `json:"data"`
    Commits string `json:"commits"`
}

type Project struct {
    Id   int64        `json:"project_id"`
    Data *ProjectData `json:"data"`
}

func main() {
    p := Project{
        Id: 1,
        Data: &ProjectData{
            Title:   "Test",
            Name:    "Mihai",
            Data:    "Some data",
            Commits: "Test Message",
        },
    }
    fmt.Println(valast.String(p))
}

输出:

go run main.go 
Project{Id: 1, Data: &ProjectData{
        Title:   "Test",
        Name:    "Mihai",
        Data:    "Some data",
        Commits: "Test Message",
}}