JSON in Go: Difference between revisions

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==Unmarshalling into Struct==
==Unmarshalling into Struct==


Using a byte slice:
===With a Byte Slice===
 
<syntaxhighlight lang='go'>
<syntaxhighlight lang='go'>
type Item struct {
type Item struct {
Line 48: Line 47:
</syntaxhighlight>
</syntaxhighlight>


===With a <tt>Reader</tt>===
Using a <code>[[Go_Package_io#Reader|Reader]]</code>:
Using a <code>[[Go_Package_io#Reader|Reader]]</code>:


=TO PROCESS=
=TO PROCESS=
<font color=darkkhaki>TO PROCESS: https://golang.cafe/blog/golang-json-marshal-example.html</font>
<font color=darkkhaki>TO PROCESS: https://golang.cafe/blog/golang-json-marshal-example.html</font>

Revision as of 19:58, 16 October 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) // pass the value

fmt.Println(string(ba))

JSON Unmarshalling JSON → Go

Unmarshalling into Struct

With a Byte Slice

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)

With a Reader

Using a Reader:

TO PROCESS

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