如何使用动态索引更新对象数组？
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【中文标题】如何使用动态索引更新对象数组？【英文标题】：How to update an array of object with a dynamic index? 【发布时间】：2020-07-20 15:13:21 【问题描述】：开始
ex "数组调整大小丢失的类或索引"
我正在构建一个对象来保存我的汽车的值。
基本逻辑是： 对于每个变速箱 > 保存每个悬架 > 保存每个车轮。
脚本逻辑：
public class VehicleController : MonoBehaviour
public gearbox[] gearboxes = new gearbox[0]; //999 not change effect
[System.Serializable]
public class gearbox
public Transform gearBoxTarget;
public List<Transform> assets = new List<Transform>();
public gearbox(Transform gearBoxTarget, List<Transform> assets )
this.gearBoxTarget = gearBoxTarget;
this.assets = assets;
void Awake()
/// count all gBox into 3d model
List<Transform> boxes = new List<Transform>();
Transform[] elems = transform.GetComponentsInChildren<Transform>();
int Index = 0;
for (int c = 0; c < elems.Length; c++)
if (elems[c].name == "gearbox")
Index++;
boxes.Add(elems[c].transform);
/// set array length (1 for gBox finded)
System.Array.Resize(ref gearboxes, Index);
/// for all gearboxes finded (or boxes.Length... It's equal)
for (int box = 0; box < gearboxes.Length; box++)
// get suspansions and wheels
Transform[] inBox = boxes[box].GetComponentsInChildren<Transform>();
List <Transform> Items = new List <Transform>();
for (int e = 0; e < inBox.Length; e++)
var el = inBox[e];
if (el.parent.name == "gearbox" || el.name == "wheel") Debug.Log(e+" => "+el); Items.Add(el); elseDebug.Log(e);
if(e==inBox.Length) Debug.Log("finder end");
/// add elements into the gearbox object
Debug.Log(gearboxes[box]); // NULL!
gearboxes[box].gearBoxTarget = boxes[box]; // NULL!
gearboxes[box].assets.AddRange(Items); // NULL!
我不明白为什么数组的长度发生了变化，尽管检查器已更新，但脚本似乎不再看到变速箱。
无论您尝试放入什么，变速箱...都是无效的
测试 02
新的简化测试。
我尝试在 Awake 中初始化列表。
它还会创建第二个列表，用于处理元素。
未能直接实例化对象我尝试将所有内容从新列表转移到旧列表。
public class VehicleController : MonoBehaviour
public gearbox[] gearboxes;
[System.Serializable]
public class gearbox
public Transform boxtarget;
public gearbox( Transform boxtarget )
this.boxtarget = boxtarget;
void Awake()
// count all gBox and set it on inspector and add to list
Transform[] elems = transform.GetComponentsInChildren<Transform>();
List<Transform> targets = new List<Transform>();
for (int c = 0; c < elems.Length; c++)
if (elems[c].name == "gearbox")
targets.Add(elems[c]);
int Counter = targets.Count;
// System.Array.Resize(ref gearboxes, Index);
gearbox[] gboxes = new gearbox[Counter];
gearboxes = new gearbox[Counter];
for (int i = 0; i < Counter; ++i)
Debug.Log(targets[i]); //ok exist
gboxes[i].boxtarget = targets[i];
System.Array.Copy(gboxes, 0, gearboxes , 0, Counter);
又一次失败。 在检查器列表中更新为 3 个元素但为空并且调试写入 null。
齿轮箱（UnityEngine.Transform）（目标确定）
NullReferenceException：对象引用未设置为 object VehicleControllerManager.VehicleController.Awake()(在
测试 03
另一种方法...
现在的尝试是将一个类添加到列表中并检索拥有该类的对象。
这样我应该绕过这样一个事实，即单声道直接指向变速箱但将其视为附加对象。
public class VehicleController : MonoBehaviour
[SerializeField]
public List<gearbox> gearboxes = new List<gearbox>();
[System.Serializable]
public class gearbox
public class box
public Transform boxTarget;
public box(Transform boxTarget)
this.boxTarget = boxTarget;
void Awake()
/// count all gBox into 3d model
List<Transform> boxes = new List<Transform>();
Transform[] elms = transform.GetComponentsInChildren<Transform>();
int Counted = 0;
for (int c = 0; c < elms.Length; c++)
if (elms[c].name == "gearbox")
Counted++; boxes.Add(elms[c].transform);
Debug.Log(boxes.Count); // yes, it's 3
/// add class on link (1 for all gBox finded)
for (int box = 0; box < boxes.Count; box++)
gearboxes.Add( new VehicleController.gearbox()); // ok, added it
/// for all gearboxes in list
for (int i = 0; i < gearboxes.Count; i++)
/// into the gearboxes get object and set values of box
//gearboxes[i].gearbox.box.boxTarget = boxes[i]; WTF? I can't navigate into the class!??
结果：检查器中出现 3 个元素，但它们内部似乎没有任何内容，或者无论如何..."gearboxes[i].gearbox.box.boxTarget = boxes[i];"我无法导航到类...
是否有可能恢复盒子并设置它们的内部值？
测试 03.b
根据各种建议和示例，我找到了一个“半解决方案”。
这不是确定的，因为我不在检查器中显示内容，而只显示插入的类。
但是，如果我循环...数据存在并返回！
public class VehicleController : MonoBehaviour
[SerializeField] public List<gearbox> gearboxes = new List<gearbox>();
[System.Serializable] public class gearbox
public _box box = new _box();
[System.Serializable]
public class _box
public Transform boxTarget get; set;
void Start()
/// count all gBox into 3d model
List<Transform> boxes = new List<Transform>();
Transform[] elms = transform.GetComponentsInChildren<Transform>();
int Counted = 0;
for (int c = 0; c < elms.Length; c++)
if (elms[c].name == "gearbox")
Counted++; boxes.Add(elms[c].transform);
Debug.Log(boxes.Count);
/// add class on link (1 for all gBox finded)
for (int box = 0; box < boxes.Count; box++)
gearboxes.Add( new VehicleController.gearbox());
// for all gearboxes in list
for (int i = 0; i < gearboxes.Count; i++)
/// add elements into the gearbox object
gearboxes[i].box.boxTarget = boxes[i];
for (int i = 0; i < gearboxes.Count; i++)
Debug.Log("++ "+gearboxes[i].box.boxTarget);
测试 03.c - 解决方案
正如建议的那样，它是“实例化对象”，但是 这是直接实例化到列表的构造。
如果没有这个，最大的问题是要理解“如果它是空的，就不可能实例化对象”，否则你会发现著名的“空错误”。
所以......让我们给它一个空！ :D，这就是解决方案！
public class VehicleController : MonoBehaviour
[SerializeField] public List<boxvalues> gearboxes = new List<boxvalues>();
[System.Serializable] public class boxvalues
public Transform boxTarget;
public boxvalues(Transform boxTarget)
this.boxTarget = boxTarget;
// [SerializeField] public Transform boxTarget get; set; // This is a safer system but does not expose variables.
void Awake()
/// count all gBox into 3d model
List<Transform> boxes = new List<Transform>(); // prepare a list of gameObject.
Transform[] elms = transform.GetComponentsInChildren<Transform>(); // find all child into main gameObject.
int Counted = 0; // Counter of gameObject
for (int c = 0; c < elms.Length; c++) // Loop all finded gameObject into main
if (elms[c].name == "gearbox") // if is my gameObject...
Counted++; boxes.Add(elms[c].transform); // add it to list and count it...
Debug.Log(boxes.Count); // yes, It's 3 gameObject.
/// add class on link (1 for all gBox finded)
for (int box = 0; box < boxes.Count; box++)
gearboxes.Add( new VehicleController.boxvalues(null)); // now for all gameObject init a new data container... empty (yooo! new list of data!)
// for all gearboxes in list
for (int i = 0; i < gearboxes.Count; i++) // now for all data container... put a new values. Win!
/// add elements into the box object
gearboxes[i].boxTarget = boxes[i];
// test return the values
for (int i = 0; i < gearboxes.Count; i++)
Debug.Log("++ "+gearboxes[i].boxTarget);
衷心感谢那些耐心给我一个有用的方向的人！
我希望这个方案对其他人有教育意义。
【问题讨论】：
如果gearbox 是一个类，那么它的默认值为null - 如果您希望它不为空，则需要创建该类的实例
如果gearbox 是class，那么您有一个对gearbox 实例的引用数组。这种引用的默认值为null
@Alberto 您不能在 c# 中调整数组的大小，只能用不同大小的新数组替换它。您或许应该考虑使用 List，因为这将提供添加/删除项目的能力。
@Alberto Array.Resize 不会调整数组的大小，它会以请求的大小创建一个新数组，并将旧数组中的元素复制到其中。这是一个技术点，但很重要，因为数组不再是同一个对象。
@Alberto，我认为问题出在 UnholySheep 解释的范围内，您正在创建一个大小正确的数组，但所有条目均为空，因为您从未将它们设置为任何内容。
【参考方案1】：
你需要创建类的实例：
public class VehicleController : MonoBehaviour
public gearbox[] gearboxes = null;
public VehicleController()
gearboxes = new gearbox[0];
[System.Serializable]
public class gearbox
public Transform gearBoxTarget;
public List<Transform> assets = new List<Transform>();
public gearbox(Transform gearBoxTarget, List<Transform> assets )
this.gearBoxTarget = gearBoxTarget;
this.assets = assets;
void Awake()
/// count all gBox into 3d model
List<Transform> boxes = new List<Transform>();
Transform[] elems = transform.GetComponentsInChildren<Transform>();
int Index = 0;
for (int c = 0; c < elems.Length; c++)
if (elems[c].name == "gearbox")
Index++;
boxes.Add(elems[c].transform);
/// set array length (1 for gBox finded)
System.Array.Resize(ref gearboxes, Index);
/// for all gearboxes finded (or boxes.Length... It's equal)
for (int box = 0; box < gearboxes.Length; box++)
// get suspansions and wheels
Transform[] inBox = boxes[box].GetComponentsInChildren<Transform>();
List <Transform> Items = new List <Transform>();
for (int e = 0; e < inBox.Length; e++)
var el = inBox[e];
if (el.parent.name == "gearbox" || el.name == "wheel") Debug.Log(e+" => "+el); Items.Add(el); elseDebug.Log(e);
if(e==inBox.Length) Debug.Log("finder end");
/// add elements into the gearbox object
Debug.Log(gearboxes[box]);
gearboxes[box].gearBoxTarget = boxes[box];
gearboxes[box].assets.AddRange(Items);
我猜你没加的函数应该是这样的：
public class Transform
public string name get; set;
public Transform parent get; set;
public Transform[] GetComponentsInChildren<T>()
return (new List<Transform>()
new Transform() name = "gearbox" ,
new Transform() parent = new Transform() name = "gearbox" , name = "wheel"
).ToArray();
假设是这种情况，逻辑相同，你必须初始化变量，因为你初始化了类，否则它总是为空。
public class VehicleController
private gearbox[] gearboxes;
private readonly Transform transform;
public VehicleController(Transform _transform)
gearboxes = new gearbox[0];
transform = _transform;
[System.Serializable]
public class gearbox
public Transform gearBoxTarget;
public List<Transform> assets = new List<Transform>();
public gearbox(Transform gearBoxTarget, List<Transform> assets)
this.gearBoxTarget = gearBoxTarget;
this.assets = assets;
void Awake()
/// count all gBox into 3d model
List<Transform> boxes = new List<Transform>();
Transform[] elems = transform.GetComponentsInChildren<Transform>();
int Index = 0;
for (int c = 0; c < elems.Length; c++)
if (elems[c].name == "gearbox")
Index++;
boxes.Add(elems[c].transform);
/// set array length (1 for gBox finded)
System.Array.Resize(ref gearboxes, Index);
/// for all gearboxes finded (or boxes.Length... It's equal)
for (int box = 0; box < gearboxes.Length; box++)
// get suspansions and wheels
Transform[] inBox = boxes[box].GetComponentsInChildren<Transform>();
List<Transform> Items = new List<Transform>();
for (int e = 0; e < inBox.Length; e++)
var el = inBox[e];
if (el.parent.name == "gearbox" || el.name == "wheel") Debug.Log(e + " => " + el); Items.Add(el); else Debug.Log(e);
if (e == inBox.Length) Debug.Log("finder end");
/// add elements into the gearbox object
Debug.Log(gearboxes[box]);
gearboxes[box].gearBoxTarget = boxes[box];
gearboxes[box].assets.AddRange(Items);
【讨论】：
不...它不起作用。一直说变速箱是空的 函数“transform.GetComponentsInChildren以上是关于如何使用动态索引更新对象数组？的主要内容，如果未能解决你的问题，请参考以下文章