ContextMenuUtil.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using Unity.Linq;
using UnityEditor;
using UnityEngine;
using UnityEngine.SceneManagement;

namespace Assets.Scripts.Editor
{
    static class BindComponentUtil
    {
        [MenuItem("CONTEXT/MonoBehaviour/BindComponensFromChildren")]
        private static void BindComponentsFromChildren(MenuCommand menuCommand)
        {
            BindComponents(menuCommand.context as MonoBehaviour, true, false);
        }

        [MenuItem("CONTEXT/MonoBehaviour/BindComponensFromScene")]
        private static void BindComponentsFromScene(MenuCommand menuCommand)
        {
            BindComponents(menuCommand.context as MonoBehaviour, true, true);
        }

        private static void BindComponents(MonoBehaviour context, bool skipBinded, bool findScene)
        {
            Debug.Log($"context.name: {context.name}");

            var contextType = context.GetType();
            Debug.Log($"contextType.Name: {contextType.Name}");

            BindFields(context, skipBinded, findScene);

            BindProperty(context, skipBinded, findScene);

            EditorUtility.SetDirty(context);
            AssetDatabase.SaveAssets();
        }


        private static void BindFields(MonoBehaviour context, bool skipBinded, bool findScene)
        {
            var contextType = context.GetType();
            Debug.Log($"contextType.Name: {contextType.Name}");

            var bindableFields = GetBindableFields(contextType).ToArray();

            foreach (var field in bindableFields)
            {
                var value = field.GetValue(context);

                if (skipBinded && value != null)
                {
                    Debug.LogWarning($"Name {field.Name} value != null");
                    continue;
                }


                var foundInChildren = false;

                // 子要素から探す
                foreach (var gameObject in context.gameObject.Descendants())
                {
                    var component = GetBindableComponent(gameObject, field.Name, field.FieldType);
                    if (component != null)
                    {
                        Debug.Log($"component {field.FieldType.Name} {field.Name} found.", gameObject);
                        field.SetValue(context, component);
                        foundInChildren = true;
                        break;
                    }
                }

                // 見つからなかった場合、シーン全体から探す
                if (!foundInChildren && findScene)
                {
                    var allGameObjects = SceneManager.GetActiveScene().GetRootGameObjects()
                        .SelectMany(x => x.DescendantsAndSelf());

                    foreach (var gameObject in allGameObjects)
                    {
                        var component = GetBindableComponent(gameObject, field.Name, field.FieldType);
                        if (component != null)
                        {
                            Debug.Log($"component {field.FieldType.Name} {field.Name} found.", gameObject);
                            field.SetValue(context, component);
                            break;
                        }
                    }
                }
            }
        }

        private static IEnumerable<FieldInfo> GetBindableFields(Type contextType)
        {
            var serializableFields = new List<FieldInfo>();

            var publicFields = contextType.GetFields(BindingFlags.Instance | BindingFlags.Public);
            serializableFields.AddRange(publicFields);

            // NonPublicなフィールドのうち、SerializeField属性が設定されてるものを取得する
            var nonPublicFields = contextType.GetFields(BindingFlags.Instance | BindingFlags.NonPublic);
            foreach (var field in nonPublicFields)
            {
                var serializeFieldAttribute = field.GetCustomAttribute<SerializeField>();

                if (serializeFieldAttribute != null)
                {
                    serializableFields.Add(field);
                }
            }

            foreach (var field in serializableFields)
            {
                var isComponentField = field.FieldType.IsSubclassOf(typeof(Component));

                if (isComponentField)
                {
                    yield return field;
                }
            }
        }


        private static void BindProperty(MonoBehaviour context, bool skipBinded, bool findScene)
        {
            var contextType = context.GetType();
            Debug.Log($"contextType.Name: {contextType.Name}");

            var bindableProperties = GetBindableProperties(contextType).ToArray();

            foreach (var property in bindableProperties)
            {
                var value = property.GetValue(context);

                if (skipBinded && value != null)
                {
                    Debug.LogWarning($"Name {property.Name} value != null");
                    continue;
                }

                var findInChildren = false;

                // 子要素から探す
                foreach (var gameObject in context.gameObject.Descendants())
                {
                    var component = GetBindableComponent(gameObject, property.Name, property.PropertyType);
                    if (component != null)
                    {
                        Debug.Log($"component {property.PropertyType.Name} {property.Name} found.", gameObject);
                        property.SetValue(context, component);
                        findInChildren = true;
                        break;
                    }
                }

                // 見つからなかった場合、シーン全体から探す
                if (!findInChildren && findScene)
                {
                    var allGameObjects = SceneManager.GetActiveScene().GetRootGameObjects()
                        .SelectMany(x => x.DescendantsAndSelf());

                    foreach (var gameObject in allGameObjects)
                    {
                        var component = GetBindableComponent(gameObject, property.Name, property.PropertyType);
                        if (component != null)
                        {
                            Debug.Log($"component {property.PropertyType.Name} {property.Name} found.", gameObject);
                            property.SetValue(context, component);
                            break;
                        }
                    }
                }
            }
        }

        private static IEnumerable<PropertyInfo> GetBindableProperties(Type contextType)
        {
            var serializableProperties = new List<PropertyInfo>();

            var publicProperties = contextType.GetProperties(BindingFlags.Instance | BindingFlags.Public);
            serializableProperties.AddRange(publicProperties);

            // NonPublicなフィールドのうち、SerializeField属性が設定されてるものを取得する
            foreach (var property in publicProperties)
            {
                if (property.Name == "transform" 
                    && property.PropertyType == typeof(Transform))
                {
                    Debug.LogWarning("skip transform");
                    continue;
                }

                var serializeFieldAttribute = property.GetCustomAttribute<SerializeField>();

                if (serializeFieldAttribute != null)
                {
                    serializableProperties.Add(property);
                }
            }

            foreach (var field in serializableProperties)
            {
                var isComponentField = field.PropertyType.IsSubclassOf(typeof(Component));

                if (isComponentField)
                {
                    yield return field;
                }
            }
        }


        private static Component GetBindableComponent(GameObject gameObject, string name, Type type)
        {
            // フィールドとオブジェクトの名前を大文字小文字無視して比較する
            if (string.Compare(gameObject.name, name, true) != 0)
            {
                // 一致しなかったらスキップ
                return null;
            }

            var childComponent = gameObject.GetComponent(type);

            return childComponent;
        }
    }
}