JSON in Go: Difference between revisions

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Line 40: Line 40:
var i Item
var i Item


err := json.Unmarshal(ba, &i)
err := json.Unmarshal(ba, &i) // pass the pointer


fmt.Printf("%+v\n", i)
fmt.Printf("%+v\n", i)

Revision as of 17:22, 25 August 2023

Internal

Overview

JSON Marshalling Go → JSON

JSON marshalling means generating a JSON representation from a Go object. It is done with json.Marshal(). The result is a byte array. To convert the byte array to a string, see:

Go Integers | Conversion between bytes and strings

Map Marshalling

Struct Marshalling

By default, only fields that start with capital letters are marshaled. The fields that start with lower caps are invisible to the marshaling process.

type Item struct {
  Color string
  Size int
  Options []string
}

i := Item{Color: "blue", Size: 5, Options: []string{"brake", "acceleration", "lights"}}

ba, err := json.Marshal(i)

fmt.Println(string(ba))

JSON Unmarshalling JSON → Go

Unmarshalling into Struct

type Item struct {
  Color string
  Size int
  Options []string
}

s := "{\"Color\":\"blue\",\"Size\":5,\"Options\":[\"brake\",\"acceleration\",\"lights\"]}"
ba := []byte(s)
var i Item

err := json.Unmarshal(ba, &i) // pass the pointer

fmt.Printf("%+v\n", i)

TO PROCESS

TO PROCESS: https://golang.cafe/blog/golang-json-marshal-example.html