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);

}
}

下面是我尝试从中提取数据的其他脚本中的代码.

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;
    }
     }
}

我可以将int值传递给其他脚本，但是即使int本来是10，它也始终为0.

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.

我的问题是我如何在脚本中保留值?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

您有很多可能性.

第一个是将您的Score设置为gameScript的静态参数.

• 因此您可以在任何地方访问它，就像这样:

• So you can access it anywhere just like that :

int myScore = gameScript.Score ;

并且声明应为:

And the declaration should be :

public static int score;

如果您要从differents脚本中保存大量的differents值，则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.

The second possibilities is far better if you want to save a lot of differents values from differents script. In this case, you need to define a gameContext singleton.

如果您不知道这是什么，则应该看一下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将允许您拥有一个gameContext实例. 在您的情况下，您的单身人士将具有得分"属性. 您将能够从任何场景和任何脚本中获取价值.

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.

这是迄今为止最好的方法.

This is the best way so far.

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