c# - assigning 'this' as reference in another script

Unity Engine
1

Hi,

I am having some problems understanding the c# below. I know all the learning resources say I should use a findobjectby method to get a reference to a script already in the scene but I am just wondering why you cannot pass a reference with this as below instead?

Warning the below will crash your program do not try

SCRIPT A - live in the scene attached to an existing gameobject i.e. game manager script / spawner script

public class ScriptA : MonoBehaviour {

public GameObject instantiateMe; // prefab with scriptB attached
int score = 0;

void Start(){
GameObject go = Instantiate(/…/) as GameObject;
ScriptB scriptB = go.GetComponent();
scriptB.scriptA = this;
}

public void updateScore(){
score++;
}

}

SCRIPT B - attached to the prefab being instantiated in Script A

public class ScriptB : MonoBehaviour {

public ScriptA scriptA;

void Start(){
scriptA.updateScore(); // fails with no error messages
}

}

2

Worked fine for me.
This was the code I used, which is just your code except I made updateScore have a capital U and I put instantiateMe inside the Instantiate and added a debug.log to make sure things were being called.
Click for code

using UnityEngine;

public class ScriptA : MonoBehaviour
{
    public GameObject instantiateMe;
    int score = 0;

    void Start()
    {
        GameObject go = Instantiate(instantiateMe) as GameObject;
        ScriptB scriptB = go.GetComponent<ScriptB>();
        scriptB.scriptA = this;
    }

    public void UpdateScore()
    {
        score++;
    }
}

using UnityEngine;

public class ScriptB : MonoBehaviour
{
    public ScriptA scriptA;

    void Start()
    {
        scriptA.UpdateScore();
        Debug.Log("Updated Score");
    }
}

I even changed the script execution order of ScriptA and ScriptB and it still worked fine.

3

Hey thanks for looking into it. Yeah it is working for me now too, must have just been a mistake in my development scripts somewhere!

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