go - 如何遍历 Golang 中的所有 YAML 值？

Question

我想了解 Golang 中的嵌套映射。我有一个如下所示的 map ，如何遍历所有键？

Data:
  - name: "foo"
    bar1: 0
      k1: val1
      k2:
         val2
         val3
    bar2: 1
      k3: val4
      k4: val5
      k3: val4
      k4: val5

Answer 1

您必须将数据解码到 map (map[interface{}]interface{} 或 map[string]interface{}) 然后您必须检查键值的类型。您可以使用 yaml.v2 包，并且可能有更清晰的界面有助于检测值的类型。否则检查迭代键并打印值的示例:

package main

import (
    "fmt"
    "gopkg.in/yaml.v2"
    "reflect"
    "strings"
)

var data = `
Data:
    - name: "foo"
      bar1: 0
      k1: val1
      k2:
         val2
         val3
      bar2: 1
      k3: val4
      k4: val5
      k5: val5
      k6: val6
`

func printVal(v interface{}, depth int) {
    typ := reflect.TypeOf(v).Kind()
    if typ == reflect.Int || typ == reflect.String {
        fmt.Printf("%s%v\n", strings.Repeat(" ", depth), v)
    } else if typ == reflect.Slice {
        fmt.Printf("\n")
        printSlice(v.([]interface{}), depth+1)
    } else if typ == reflect.Map {
        fmt.Printf("\n")
        printMap(v.(map[interface{}]interface{}), depth+1)
    }

}

func printMap(m map[interface{}]interface{}, depth int) {
    for k, v := range m {
        fmt.Printf("%sKey:%s", strings.Repeat(" ", depth), k.(string))
        printVal(v, depth+1)
    }
}

func printSlice(slc []interface{}, depth int) {
    for _, v := range slc {
        printVal(v, depth+1)
    }
}

func main() {
    m := make(map[string]interface{})

    err := yaml.Unmarshal([]byte(data), &m)
    if err != nil {
        panic(err)
    }
    for k, v := range m {
        fmt.Printf("Key:%s ", k)
        printVal(v, 1)
    }
}