Unity3D在瞬间获取NullReferenceException

正如标题所说。我在一瞬间得到一个NullReferenceException，在那之后，一切正常。谁能告诉我为什么会这样

这是我的代码，错误来自第43行：

    #pragma strict
//NOTE: Display the health of the enemy that is targetted by the player!

//private var enemyGO : GameObject;
//private var enemyScript : EnemyAI;

var healthText : GUIText;


var myPlayer : Transform;
var myPlayerScript : PlayerScript;

var myPlayerTarget : Transform;
var myPlayerTargetScript : EnemyAI;


function Start () {
    myPlayer = GameObject.FindGameObjectWithTag("Player").transform;
    myPlayerScript = myPlayer.GetComponent("PlayerScript");

/*  if (myPlayerScript.target != null) {
        myPlayerTarget = myPlayerScript.target;

        myPlayerTarget.GetComponent("EnemyAI");
    }*/

//  enemyGO = GameObject.Find("Enemy");
//  enemyScript = enemyGO.GetComponent("EnemyAI");
}


function FixedUpdate () {
    if (myPlayerScript.target != null) {
        myPlayerTarget = myPlayerScript.target;

        myPlayerTargetScript = myPlayerTarget.GetComponent("EnemyAI");
    }
}


function OnGUI () {
    if (myPlayerScript.target != null) {
        GUI.Label (Rect (((Screen.width / 2) + Screen.width / 3), 16, 250, 20), "EnemyHP: " + (Mathf.Round(myPlayerTargetScript.curHealth)) + " / " + /*(Mathf.Round(*/myPlayerTargetScript.maxHealth/*))*/);
    }
}

谢谢：）

编辑：这不显示行：p

---

所以错误发生在GUI.Label中。。。my OnGUI函数中的行：）

既然您已经在myPlayerTargetScript中持有对您的EnemyAI脚本的引用，您应该在OnGUI中检查它是否为null

也不要对这些事情使用FixeUpdate。FixeUpdate属于物理系统。只需使用更新即可：

 #pragma strict

var healthText : GUIText;

var myPlayer : Transform;
var myPlayerScript : PlayerScript;

var myPlayerTarget : Transform;
var myPlayerTargetScript : EnemyAI;


function Start () {
    myPlayer = GameObject.FindGameObjectWithTag("Player").transform;
    myPlayerScript = myPlayer.GetComponent(PlayerScript);
}

function Update () {
    if (myPlayerScript.target != null) {
        myPlayerTarget = myPlayerScript.target;

        myPlayerTargetScript = myPlayerTarget.GetComponent(EnemyAI);
    }
}

function OnGUI () {
    if (myPlayerTargetScript  != null) {
        GUI.Label (Rect (((Screen.width / 2) + Screen.width / 3), 16, 250, 20), "EnemyHP: " + (Mathf.Round(myPlayerTargetScript.curHealth)) + " / " + myPlayerTargetScript.maxHealth);
    }
}

---

ps：在将脚本发布到这里之前，您应该先整理一下；）

完全错误是什么？OnGUI中有几个变量可能是

null

，具体取决于实现：

myPlayerTargetScript

，

myPlayerTargetScript.curHealth

，

myPlayerTargetScript.maxHealth

啊，很抱歉我忘了，这里是：NullReferenceException:Object reference未设置为对象EnemyHealthScript.OnGUI（）的实例（位于Assets/Standard Assets/prefables/Sources/Scripts/EnemyHealthScript.js:43）是的，就像我说的，很可能是

myPlayerTargetScript

或其某个字段为空。没有看到你的整个项目，那只是猜测。这可能是因为

myPlayerScript

最初没有

target

，这将跳过设置

myPlayerTargetScript

的可能重复项