GameObject.FindGameObjectsWithTag

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

public static GameObject[] **FindGameObjectsWithTag** (string **tag**);

## 参数

| tag | 在搜索 `GameObjects` 时所针对的标签的名称。 |
| ----- | ------------------------------------------------- |

## 描述

返回标签为 `tag` 的活动 GameObjects 的数组。如果未找到任何 GameObject，则返回空数组。

标签在使用前必须在标签管理器中加以声明。如果此标签不存在，或者传递了空字符串或 `null` 作为标签，则将抛出 `UnityException`。

```
// Instantiates respawnPrefab at the location
// of all game objects tagged "Respawn".

using UnityEngine;
using System.Collections;

public class ExampleClass : MonoBehaviour
{
    public GameObject respawnPrefab;
    public GameObject[] respawns;
    void Start()
    {
        if (respawns == null)
            respawns = GameObject.FindGameObjectsWithTag("Respawn");

foreach (GameObject respawn in respawns)
        {
            Instantiate(respawnPrefab, respawn.transform.position, respawn.transform.rotation);
        }
    }
}
```

另一个示例：

```
// Find the name of the closest enemy

using UnityEngine;
using System.Collections;

public class ExampleClass : MonoBehaviour
{
    public GameObject FindClosestEnemy()
    {
        GameObject[] gos;
        gos = GameObject.FindGameObjectsWithTag("Enemy");
        GameObject closest = null;
        float distance = Mathf.Infinity;
        Vector3 position = transform.position;
        foreach (GameObject go in gos)
        {
            Vector3 diff = go.transform.position - position;
            float curDistance = diff.sqrMagnitude;
            if (curDistance < distance)
            {
                closest = go;
                distance = curDistance;
            }
        }
        return closest;
    }
}
```

另一个示例，测试空数组：

```
using UnityEngine;

// Search for game objects with a tag that is not used

public class Example : MonoBehaviour
{
    void Start()
    {
        GameObject[] gameObjects;
        gameObjects = GameObject.FindGameObjectsWithTag("Enemy");

if (gameObjects.Length == 0)
        {
            Debug.Log("No game objects are tagged with 'Enemy'");
        }
    }
}
```