Unity2D无法跳转

Question

按向上箭头键时无法跳跃。 当我移除 isGrounded 的条件以能够跳跃时，那么我的角色就可以在空中跳跃。

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

public class PlayerMovement : MonoBehaviour
{
    [SerializeField] private float speed;
    private Rigidbody2D body;
    bool isGrounded;

    private void Awake()
    {
        body = GetComponent<Rigidbody2D>();
    }

    private void Update()
    {
        float HorizontalInput = Input.GetAxis("Horizontal");
        body.velocity = new Vector3(Input.GetAxis("Horizontal") * speed, body.velocity.y);

        if (HorizontalInput < -0.01f)
            transform.localScale = Vector3.one;
        else if (HorizontalInput > 0.01f)
            transform.localScale = new Vector3(-1, 1, 1);
        
        if (Input.GetKey(KeyCode.UpArrow))
            isGrounded = false;

        if (Input.GetKey(KeyCode.UpArrow) && isGrounded)
            body.velocity = new Vector2(body.velocity.x, speed);
    }

    private void OnCollisionEnter2D()
    {
        isGrounded = true;
    }
}

我尝试使用 OnCollisionEnter2D 将 isGrounded 设置为 true，但我认为它不起作用。

Answer 1

问题出在这个逻辑上：

        if (Input.GetKey(KeyCode.UpArrow))
            isGrounded = false;

        // isGrounded will always be false here if up-arrow key is pressed.
        if (Input.GetKey(KeyCode.UpArrow) && isGrounded)
            body.velocity = new Vector2(body.velocity.x, speed);

你在找什么：

        if (Input.GetKey(KeyCode.UpArrow) && isGrounded) {
            body.velocity = new Vector2(body.velocity.x, speed);
            isGrounded = false;
        }

使用大括号表示语句下的多行代码。

此外， 使用 FixedUpdate 进行与物理相关的操作，例如 Rigidbodies 。