Transform.GetSiblingIndex

# [Transform](https://docs.unity3d.com/cn/2019.4/ScriptReference/Transform.html).GetSiblingIndex

public int **GetSiblingIndex** ();

## 描述

获取同级索引。

用于返回 GameObject 的同级索引。如果 GameObject 与其他 GameObject 共享一个父级并且处于同一级别（即它们共享相同的直接父级），则这些 GameObject 被称为同级对象。同级索引显示每个 GameObject 在该同级层级视图中的位置。

使用 GetSiblingIndex 查找 GameObject 在该层级视图中的位置。当 GameObject 的同级索引发生更改时，其在“Hierarchy”窗口中的顺序也会改变。如果您需要更改 GameObject 子项的排序（例如使用布局组组件时），这很有用。

布局组还将按索引以可视化方式对组进行重新排序。要了解有关布局组的更多信息，请参阅 [AutoLayout](https://docs.unity3d.com/cn/2019.4/Manual/comp-UIAutoLayout.html)。 要设置 GameObject 的同级索引，请参阅 [Transform.SetSiblingIndex](https://docs.unity3d.com/cn/2019.4/ScriptReference/Transform.SetSiblingIndex.html)。

```
//This script demonstrates how to return (GetSiblingIndex) and change (SetSiblingIndex) the sibling index of a GameObject.
//Attach this script to the GameObject you would like to change the sibling index of.
//To see this in action, make this GameObject the child of another GameObject, and create siblings for it.

using UnityEngine;

public class TransformGetSiblingIndex : MonoBehaviour
{
    //Use this to change the hierarchy of the GameObject siblings
    int m_IndexNumber;

void Start()
    {
        //Initialise the Sibling Index to 0
        m_IndexNumber = 0;
        //Set the Sibling Index
        transform.SetSiblingIndex(m_IndexNumber);
        //Output the Sibling Index to the console
        Debug.Log("Sibling Index : " + transform.GetSiblingIndex());
    }

void OnGUI()
    {
        //Press this Button to increase the sibling index number of the GameObject
        if (GUI.Button(new Rect(0, 0, 200, 40), "Add Index Number"))
        {
            //Make sure the index number doesn't exceed the Sibling Index by more than 1
            if (m_IndexNumber <= transform.GetSiblingIndex())
            {
                //Increase the Index Number
                m_IndexNumber++;
            }
        }

//Press this Button to decrease the sibling index number of the GameObject
        if (GUI.Button(new Rect(0, 40, 200, 40), "Minus Index Number"))
        {
            //Make sure the index number doesn't go below 0
            if (m_IndexNumber >= 1)
            {
                //Decrease the index number
                m_IndexNumber--;
            }
        }
        //Detect if any of the Buttons are being pressed
        if (GUI.changed)
        {
            //Update the Sibling Index of the GameObject
            transform.SetSiblingIndex(m_IndexNumber);
            Debug.Log("Sibling Index : " + transform.GetSiblingIndex());
        }
    }
}
```