Go-json解码到接口及根据键获取值
Go-json解码到接口及根据键获取值
package main
import (
"encoding/json"
"fmt"
"github.com/bitly/go-simplejson"
)
type JsonServer struct {
ServerName string
ServerIP string
}
type JsonServers struct {
Servers []JsonServer
}
func main() {
var s JsonServers
str := `{"servers":[{"serverName":"Shanghai_VPN","serverIP":"127.0.0.1"},{"serverName":"Beijing_VPN","serverIP":"127.0.0.2"}]}`
json.Unmarshal([]byte(str), &s)
fmt.Println(s) //{[{Shanghai_VPN 127.0.0.1} {Beijing_VPN 127.0.0.2}]}
b := []byte(`{"Name":"Wednesday","Age":6,"Parents":["Gomez","Morticia"]}`)
var f interface{}
json.Unmarshal(b, &f)
fmt.Printf("%+v\n", f) // map[Name:Wednesday Age:6 Parents:[Gomez Morticia]]
m := f.(map[string]interface{})
for k, v := range m {
switch vv := v.(type) {
case string:
fmt.Println(k, "is string", vv) //Name is string Wednesday
case int:
fmt.Println(k, "is int", vv)
case float64:
fmt.Println(k, "is float64", vv) //Age is float64 6
case []interface{}:
fmt.Println(k, "is an array:") //Parents is an array:
//0 Gomez
//1 Morticia
for i, u := range vv {
fmt.Println(i, u)
}
default:
fmt.Println(k, "is of a type I don't know how to handle")
}
}
/**
如您所见,我们现在可以通过interface{}解析未知格式的JSON并键入断言。
以上示例是官方解决方案,但类型断言并不总是方便。
因此,我推荐一个名为simplejson的开源项目,由bitly创建和维护。
以下是如何使用此项目处理未知格式的JSON的示例:
go get ithub.com/bitly/go-simplejson
*/
// 根据键获取值
js, err := simplejson.NewJson([]byte(`{
"test": {
"array": [1, "2", 3],
"int": 10,
"float": 5.150,
"bignum": 9223372036854775807,
"string": "simplejson",
"bool": true
}
}`))
if err != nil {
fmt.Println("err:", err)
}
arr, _ := js.Get("test").Get("array").Array() //arr: [1 2 3]
fmt.Println("arr:", arr)
i, _ := js.Get("test").Get("int").Int() //i: 10
fmt.Println("i:", i)
ms := js.Get("test").Get("string").MustString() //ms: simplejson
fmt.Println("ms:", ms)
}
json解码到接口
package main
import (
"encoding/json"
"fmt"
)
func main() {
jsonBuf := `
{
"company": "itcast",
"subjects": [
"Go",
"C++",
"Python",
"Test"
],
"isok": true,
"price": 666.666
}
`
//创建一个map
m := make(map[string]interface{}, 4)
err := json.Unmarshal([]byte(jsonBuf), &m)
if err != nil {
fmt.Println("err=", err)
return
}
fmt.Println("m=", m) //m= map[company:itcast subjects:[Go C++ Python Test] isok:true price:666.666]
fmt.Printf("m=%+v\n", m) //m=map[isok:true price:666.666 company:itcast subjects:[Go C++ Python Test]]
var s string
s = m["company"].(string)
fmt.Println("s= ", s) //s= itcast
var s1 bool
s1 = m["isok"].(bool)
fmt.Println("s1= ", s1) //s1= true
var s2 float64
s2 = m["price"].(float64)
fmt.Println("s2= ", s2) //s2= 666.666
var str string
//类型断言
for key, value := range m {
// fmt.Printf("%v===>%v\n", key, value)
switch data := value.(type) {
case string:
str = data
fmt.Printf("map[%s]的值类型为string,内容为%s\n", key, str)
case bool:
fmt.Printf("map[%s]的值类型为bool,内容为%v\n", key, data)
case float64:
fmt.Printf("map[%s]的值类型为float64,内容为%v\n", key, data)
case []string:
fmt.Printf("map[%s]的值类型为[]stiring1,内容为%v\n", key, data)
case []interface{}:
fmt.Printf("map[%s]的值类型为[]stiring2,内容为%v\n", key, data)
}
/*
map[company]的值类型为string,内容为itcast
map[subjects]的值类型为[]stiring2,内容为[Go C++ Python Test]
map[isok]的值类型为bool,内容为true
map[price]的值类型为float64,内容为666.666
*/
}
}