Collider2D.OnTriggerEnter2D(Collider2D)

参数

描述

当另一个对象进入附加到该对象的触发碰撞体时发送（仅限 2D 物理）。

在调用期间传入的 Collider2D 参数中报告有关其他碰撞体的进一步信息。

触发器事件将发送到已禁用的 MonoBehaviours，以便允许启用 Behaviours，以响应碰撞。

请参阅：Collider2D 类以及 OnTriggerExit2D 和 OnTriggerStay2D 消息。

此处显示了一个 OnTriggerEnter2D 示例。此示例有两个空的 GameObject，分别名为 GameObject1 和 /GameObject2/。这两个游戏对象都有脚本文件能使本示例正常工作。第一个脚本是 /Example1/，用于创建 Sprite 并添加 BoxCollider2D 和 Rigidbody2D。此对象受重力下落并与 Example2 发生碰撞。Example2 无法看到显示效果。（它创建的矩形在 Scene 窗口中可见。）这两个 GameObject 都会报告碰撞。

以下脚本是 Example1。

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

// Create GameObject1 that falls under gravity.  It will pass through
// Example2 and cause a collision.  GameObject1 is moved back to
// the start position and it will again start to fall under gravity.

public class Example1 : MonoBehaviour
{
    void Awake()
    {
        SpriteRenderer sr;
        sr = gameObject.AddComponent<SpriteRenderer>() as SpriteRenderer;
        sr.color = new Color(0.9f, 0.9f, 0.1f, 1.0f);

        BoxCollider2D bc;
        bc = gameObject.AddComponent<BoxCollider2D>() as BoxCollider2D;
        bc.size = new Vector2(1.0f, 1.0f);

        Rigidbody2D rb;
        rb = gameObject.AddComponent<Rigidbody2D>() as Rigidbody2D;
        rb.gravityScale = 1.0f;

        // A square in the Resources folder is used.
        gameObject.GetComponent<SpriteRenderer>().sprite = Resources.Load<Sprite>("square");

        // GameObject1 starts 3 units in the Up direction.
        gameObject.transform.position = new Vector3(0.0f, 3.0f, 0.0f);
        gameObject.transform.localScale = new Vector3(0.5f, 0.5f, 1.0f);
    }

    private float timer = 0.0f;
    private bool restart = false;

    void FixedUpdate()
    {
        if (restart == true)
        {
            timer = timer + Time.deltaTime;
            if (timer > 0.25f)
            {
                gameObject.transform.position = new Vector3(0.0f, 3.0f, 0.0f);
                gameObject.GetComponent<Rigidbody2D>().velocity = new Vector2(0.0f, 0.0f);
                restart = false;
            }
        }
    }

    // called when this GameObject collides with GameObject2.
    void OnTriggerEnter2D(Collider2D col)
    {
        Debug.Log("GameObject1 collided with " + col.name);
        restart = true;
        timer = 0.0f;
    }
}

这是 /Example2/，即第二个 GameObject 的碰撞脚本：

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

// Create a rectangle that the other GameObject will collide with.
// Note that this GameObject has no visibility.
// (View in the Scene view to see this GameObject.)

public class Example2 : MonoBehaviour
{
    void Awake()
    {
        BoxCollider2D bc;
        bc = gameObject.AddComponent<BoxCollider2D>() as BoxCollider2D;
        bc.size = new Vector2(3.0f, 1.0f);
        bc.isTrigger = true;

        gameObject.transform.localScale = new Vector3(3.0f, 1.0f, 1.0f);
        gameObject.transform.position = new Vector3(0.0f, -2.0f, 0.0f);
    }

    void OnTriggerEnter2D(Collider2D col)
    {
        Debug.Log("GameObject2 collided with " + col.name);
    }
}