"Go getValueFromPath()"의 두 판 사이의 차이

2025년 3월 11일 (화) 14:27 기준 최신판

1 개요[ | ]

Go getValueFromPath()

2 struct[ | ]

package main

import (
	"fmt"
	"reflect"
	"strings"
)

type User struct {
	Name    string
	Profile Profile
}

type Profile struct {
	Email string
	Phone string
}

func main() {
	user := User{
		Name: "John Doe",
		Profile: Profile{
			Email: "john.doe@example.com",
			Phone: "123-456-7890",
		},
	}

	fmt.Println(getValueFromPath(user, "X"))             // <nil>
	fmt.Println(getValueFromPath(user, "Name"))          // "John Doe"
	fmt.Println(getValueFromPath(user, "Profile"))       // {john.doe@example.com 123-456-7890}
	fmt.Println(getValueFromPath(user, "Profile.Email")) // "john.doe@example.com"
	fmt.Println(getValueFromPath(user, "Profile.Phone")) // "123-456-7890"
}

func getValueFromPath(v interface{}, path string) interface{} {
	fields := strings.Split(path, ".")
	rv := reflect.ValueOf(v)
	for _, field := range fields {
		rv = rv.FieldByName(field)
		if !rv.IsValid() {
			return nil
		}
	}
	return rv.Interface()
}

3 json[ | ]

package main

import (
	"fmt"
	"reflect"
	"strings"
)

type User struct {
	Name    string  `json:"name"`
	Profile Profile `json:"profile"`
}

type Profile struct {
	Email string `json:"email"`
	Phone string `json:"phone"`
}

func main() {
	user := User{
		Name: "John Doe",
		Profile: Profile{
			Email: "john.doe@example.com",
			Phone: "123-456-7890",
		},
	}

	fmt.Println(getValueFromPath(user, "x"))             // <nil>
	fmt.Println(getValueFromPath(user, "name"))          // "John Doe"
	fmt.Println(getValueFromPath(user, "profile"))       // {john.doe@example.com 123-456-7890}
	fmt.Println(getValueFromPath(user, "profile.email")) // "john.doe@example.com"
	fmt.Println(getValueFromPath(user, "profile.phone")) // "123-456-7890"
}

func getValueFromPath(v interface{}, path string) interface{} {
	fields := strings.Split(path, ".")
	rv := reflect.ValueOf(v)

	for _, field := range fields {
		rv = reflect.Indirect(rv)

		switch rv.Kind() {
		case reflect.Struct:
			rv = rv.FieldByNameFunc(func(name string) bool {
				fieldType, _ := rv.Type().FieldByName(name)
				jsonTag := fieldType.Tag.Get("json")
				return jsonTag == field || strings.EqualFold(name, field)
			})

		default:
			return nil
		}

		if !rv.IsValid() {
			return nil
		}
	}

	return rv.Interface()
}

4 같이 보기[ | ]

lodash get()

@@ 2번째 줄: / 2번째 줄: @@
 ;Go getValueFromPath()
+==struct==
 <syntaxhighlight lang='go'>
 package main
@@ 30번째 줄: / 31번째 줄: @@
 	}
-	fmt.Println(getValueFromPath(user, ".X"))             // <nil>
+	fmt.Println(getValueFromPath(user, "X"))             // <nil>
-	fmt.Println(getValueFromPath(user, ".Name"))          // "John Doe"
+	fmt.Println(getValueFromPath(user, "Name"))          // "John Doe"
-	fmt.Println(getValueFromPath(user, ".Profile"))       // {john.doe@example.com 123-456-7890}
+	fmt.Println(getValueFromPath(user, "Profile"))       // {john.doe@example.com 123-456-7890}
-	fmt.Println(getValueFromPath(user, ".Profile.Email")) // "john.doe@example.com"
+	fmt.Println(getValueFromPath(user, "Profile.Email")) // "john.doe@example.com"
-	fmt.Println(getValueFromPath(user, ".Profile.Phone")) // "123-456-7890"
+	fmt.Println(getValueFromPath(user, "Profile.Phone")) // "123-456-7890"
 }
 func getValueFromPath(v interface{}, path string) interface{} {
-	fields := strings.Split(path[1:], ".")
+	fields := strings.Split(path, ".")
 	rv := reflect.ValueOf(v)
 	for _, field := range fields {
@@ 49번째 줄: / 50번째 줄: @@
 }
 </syntaxhighlight>
+==json==
 <syntaxhighlight lang='go'>
 package main
 import (
-	"encoding/json"
 	"fmt"
 	"reflect"
@@ 70번째 줄: / 72번째 줄: @@
 func main() {
-	jsonData := `{
+	user := User{
-		"name": "John Doe",
+		Name: "John Doe",
-		"profile": {
+		Profile: Profile{
-			"email": "john.doe@example.com",
+			Email: "john.doe@example.com",
-			"phone": "123-456-7890"
+			Phone: "123-456-7890",
-		}
+		},
-	}`
-	var user User
-	if err := json.Unmarshal([]byte(jsonData), &user); err != nil {
-		fmt.Println("Error unmarshalling JSON:", err)
-		return
 	}
-	fmt.Println(getValueFromPath(user, ".name"))          // "John Doe"
+	fmt.Println(getValueFromPath(user, "x"))             // <nil>
-	fmt.Println(getValueFromPath(user, ".profile"))       // {john.doe@example.com 123-456-7890}
+	fmt.Println(getValueFromPath(user, "name"))          // "John Doe"
-	fmt.Println(getValueFromPath(user, ".profile.email")) // "john.doe@example.com"
+	fmt.Println(getValueFromPath(user, "profile"))       // {john.doe@example.com 123-456-7890}
-	fmt.Println(getValueFromPath(user, ".profile.phone")) // "123-456-7890"
+	fmt.Println(getValueFromPath(user, "profile.email")) // "john.doe@example.com"
+	fmt.Println(getValueFromPath(user, "profile.phone")) // "123-456-7890"
 }
 func getValueFromPath(v interface{}, path string) interface{} {
-	fields := strings.Split(strings.TrimPrefix(path, "."), ".")
+	fields := strings.Split(path, ".")
 	rv := reflect.ValueOf(v)
@@ 97번째 줄: / 94번째 줄: @@
 		rv = reflect.Indirect(rv)
-		rt := rv.Type()
+		switch rv.Kind() {
-		found := false
+		case reflect.Struct:
+			rv = rv.FieldByNameFunc(func(name string) bool {
+				fieldType, _ := rv.Type().FieldByName(name)
+				jsonTag := fieldType.Tag.Get("json")
+				return jsonTag == field || strings.EqualFold(name, field)
+			})
-		for i := 0; i < rt.NumField(); i++ {
+		default:
-			structField := rt.Field(i)
+			return nil
-			jsonTag := structField.Tag.Get("json")
-			if jsonTag == field {
-				rv = rv.Field(i)
-				found = true
-				break
-			}
 		}
-		if !found || !rv.IsValid() {
+		if !rv.IsValid() {
 			return nil
 		}
@@ 119번째 줄: / 114번째 줄: @@
 }
 </syntaxhighlight>
+==같이 보기==
+* [[lodash get()]]
 [[분류: Go 구조체]]