github.com/roboticscm/goman@v0.0.0-20210203095141-87c07b4a0a55/doc/progs/json3.go (about)

     1  // compile
     2  
     3  // Copyright 2012 The Go Authors. All rights reserved.
     4  // Use of this source code is governed by a BSD-style
     5  // license that can be found in the LICENSE file.
     6  
     7  package main
     8  
     9  import (
    10  	"encoding/json"
    11  	"fmt"
    12  	"log"
    13  	"reflect"
    14  )
    15  
    16  func Decode() {
    17  	b := []byte(`{"Name":"Wednesday","Age":6,"Parents":["Gomez","Morticia"]}`)
    18  
    19  	var f interface{}
    20  	err := json.Unmarshal(b, &f)
    21  
    22  	// STOP OMIT
    23  
    24  	if err != nil {
    25  		panic(err)
    26  	}
    27  
    28  	expected := map[string]interface{}{
    29  		"Name": "Wednesday",
    30  		"Age":  float64(6),
    31  		"Parents": []interface{}{
    32  			"Gomez",
    33  			"Morticia",
    34  		},
    35  	}
    36  
    37  	if !reflect.DeepEqual(f, expected) {
    38  		log.Panicf("Error unmarshalling %q, expected %q, got %q", b, expected, f)
    39  	}
    40  
    41  	f = map[string]interface{}{
    42  		"Name": "Wednesday",
    43  		"Age":  6,
    44  		"Parents": []interface{}{
    45  			"Gomez",
    46  			"Morticia",
    47  		},
    48  	}
    49  
    50  	// STOP OMIT
    51  
    52  	m := f.(map[string]interface{})
    53  
    54  	for k, v := range m {
    55  		switch vv := v.(type) {
    56  		case string:
    57  			fmt.Println(k, "is string", vv)
    58  		case int:
    59  			fmt.Println(k, "is int", vv)
    60  		case []interface{}:
    61  			fmt.Println(k, "is an array:")
    62  			for i, u := range vv {
    63  				fmt.Println(i, u)
    64  			}
    65  		default:
    66  			fmt.Println(k, "is of a type I don't know how to handle")
    67  		}
    68  	}
    69  
    70  	// STOP OMIT
    71  }
    72  
    73  func main() {
    74  	Decode()
    75  }