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|
package main
import (
"encoding/json"
"fmt"
"log"
)
const jsonData = `[
"foo",
"bar"
]`
const jsonData2 = `[
{"foo": "foo"},
{"bar": "bar"}
]`
const jsonData3 = `{
"foo": "foo",
"bar": "bar"
}`
func fromSlice() {
var a []interface{}
var c, d interface{}
c = 2
d = 3
a = []interface{}{c, d}
if err := json.Unmarshal([]byte(jsonData), &a); err != nil {
log.Fatalln(err)
}
for k, v := range a {
fmt.Println(k, ":", v)
}
}
func fromEmpty() {
var a interface{}
var c, d interface{}
c = 2
d = 3
a = []interface{}{c, d}
if err := json.Unmarshal([]byte(jsonData), &a); err != nil {
log.Fatalln(err)
}
b := a.([]interface{})
for k, v := range b {
fmt.Println(k, ":", v)
}
}
func sliceOfObjects() {
var a interface{}
if err := json.Unmarshal([]byte(jsonData2), &a); err != nil {
log.Fatalln(err)
}
b := a.([]interface{})
for k, v := range b {
fmt.Println(k, ":", v)
}
}
func intoMap() {
var a interface{}
if err := json.Unmarshal([]byte(jsonData3), &a); err != nil {
log.Fatalln(err)
}
b := a.(map[string]interface{})
seenFoo := false
for k, v := range b {
vv := v.(string)
if vv != "foo" {
if seenFoo {
fmt.Println(k, ":", vv)
break
}
kk := k
vvv := vv
defer fmt.Println(kk, ":", vvv)
continue
}
seenFoo = true
fmt.Println(k, ":", vv)
}
}
func main() {
fromSlice()
fromEmpty()
sliceOfObjects()
intoMap()
}
// Output:
// 0 : foo
// 1 : bar
// 0 : foo
// 1 : bar
// 0 : map[foo:foo]
// 1 : map[bar:bar]
// foo : foo
// bar : bar
|
