Unity C# 空引用异常 [英] Unity C# Null Reference Exception

问题描述

我正在尝试使用 C# 代码从 Unity 中的 int 变量获取数据.下面是我用来获取 int 的 C# 代码.

I am trying to get data from an int variable in Unity using C# code. Below is the C# code I am using to get the int.

using UnityEngine;
using System.Collections;

public class endGameMessage : MonoBehaviour {
public static int score2;

void Start () {
    GameObject thePlayer = GameObject.FindWithTag("Player");
    gameScript game = thePlayer.GetComponent<gameScript>();
    score2 = game.score;
}

// Update is called once per frame
void Update () {

    Debug.Log (score2);

}
}

下面是我试图从中提取数据的另一个脚本中的代码.

Below is the code from the other script I am trying to pull the data from.

using UnityEngine;
using System.Collections;

public class gameScript : MonoBehaviour {
//score
public int score = 0;
void OnTriggerEnter(Collider other) {
    if(other.gameObject.tag =="hammer"){
        GameObject.FindGameObjectWithTag("pickUpMessage").guiText.text = ("Picked Up A Hammer");    

        Destroy(other.gameObject);
        Debug.Log("collision detected hammer");
        audio.PlayOneShot(gotHit);
        score = score+10;
    }
     }
}

我可以让 int 值遇到另一个脚本，但它总是 0，即使 int 本来是 10.

I can get the the int value to come across to the other script but its always 0 even if the int was meant to be 10.

我的问题是如何在脚本中保持值?任何帮助表示赞赏.

My question is how would i keep the value across the scripts? Any help is appreciated.

推荐答案

你有很多可能性.

第一个是将您的 Score 设置为游戏脚本的静态参数.

• 这样你就可以在任何地方访问它:

• So you can access it anywhere just like that :

int myScore = gameScript.Score ;

声明应该是:

And the declaration should be :

public static int score;

如果你想从不同的脚本中保存很多不同的值，第二种可能性要好得多.在这种情况下，您需要定义一个 gameContext 单例.

如果你不知道这是什么，你应该看看 C# 中的单例:[https://msdn.microsoft.com/en-us/library/ff650316.aspx]

If you don't know what is this, you should take a look at singleton in C# : [https://msdn.microsoft.com/en-us/library/ff650316.aspx]

Singleton 将允许您拥有游戏上下文的单个实例.在您的情况下，您的单身人士将有一个 Score 属性.您将能够从任何场景和任何脚本中获得价值.

Singleton will allow you to have a single instance of your gameContext. In your case, your singleton will have a Score attribute. And you will be able to get the value from any scene and any scripts.

这是目前最好的方法.

这篇关于Unity C# 空引用异常的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！