GameObject.FindGameObjectsWithTag

Parameters

Description

Returns an array of active GameObjects tagged tag. Returns empty array if no GameObject was found.

Tags must be declared in the tag manager before using them. A UnityException will be thrown if the tag does not exist or an empty string or null is passed as the tag.

// 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);
        }
    }
}

Another example:

// 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;
    }
}

Another example, testing for empty array:

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'");
        }
    }
}