An object reference is required for the non-static field, method, or property problem

Unity Engine
1

I’m working on a card game and here it is my error and code can anyone help me?

**Error:**Assets\Scripts\ThisCard.cs(49,31): error CS0120: An object reference is required for the non-static field, method, or property 'PlayerDeck.deckSize

Code:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
using UnityEngine.EventSystems;


public class ThisCard : MonoBehaviour
{

    public List<Card> thisCard = new List<Card>();
    public int thisId;

    public int id;
    public string cardName;
    public int cost;
    public int power;
    public string cardDescription;

    public Text nameText;
    public Text costText;
    public Text powerText;
    public Text descriptionText;

    public Sprite thisSprite;
    public Image thatImage;

    public Image frame;

    public bool cardBack;
    public static bool staticCardBack; //
    CardBack CardBackScript;

    public GameObject Hand;
    public int numberOfCardsInDeck;


   





    // Start is called before the first frame update
    void Start()
    {


        numberOfCardsInDeck = PlayerDeck.deckSize;

        CardBackScript = GetComponent<CardBack>();

        thisCard[0] = CardDatabase.cardList[thisId];

       
       
       
    }

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

       


        id = thisCard[0].id;
        cardName = thisCard[0].cardName;
        cost = thisCard[0].cost;
        power = thisCard[0].power;
        cardDescription = thisCard[0].cardDescription;

        thisSprite = thisCard[0].thisImage;



        nameText.text = "" + cardName;
        costText.text = "" + cost;
        powerText.text = "" + power;
        descriptionText.text = "" + cardDescription;

        thatImage.sprite = thisSprite;


        switch (thisCard[0].color)
        {
            case "Red":
                frame.GetComponent<Image>().color = new Color32(255, 0, 0, 255);
                break;

            case "Blue":
                frame.GetComponent<Image>().color = new Color32(0, 0, 255, 255);
                break;

            case "Brown":
                frame.GetComponent<Image>().color = new Color32(153, 76, 0, 255);
                break;

            case "Yellow":
                frame.GetComponent<Image>().color = new Color32(255, 255, 0, 255);
                break;

            default:
                frame.GetComponent<Image>().color = new Color32(30, 30, 30, 255);
                break;
        }

        staticCardBack = cardBack; //
        //CardBackScript.UpdateCard(cardBack); //

       

    }
}
2

What is PlayerDeck? You don’t reference it anywhere else. That will probably answer your question.

1 Like
3

Hello, thanks for answer.

I’m making this tutorial.
PlayerDeck is another script in this project. I did exactly same things but my PlayerDeck keep getting error. If need i can send my PlayerDeck.cs

4

In the tutorial, the line inside of PlayerDeck is

public static int deckSize;

The error is telling you that you didn’t make it static, therefore it can’t access it because that variable was only made for objects.

2 Likes
5

No need for that, you likely just have an error in copying it from the tutorial.

I’ll guess that your .deckSize property is supposed to either be static or const, or you have done some other part wrong that is supposed to make a PlayerDeck instance.

Tutorials and example code are great, but keep this in mind to maximize your success and minimize your frustration:

How to do tutorials properly, two (2) simple steps to success:

Step 1. Follow the tutorial and do every single step of the tutorial 100% precisely the way it is shown. Even the slightest deviation (even a single character!) generally ends in disaster. That’s how software engineering works. Every step must be taken, every single letter must be spelled, capitalized, punctuated and spaced (or not spaced) properly, literally NOTHING can be omitted or skipped.
Fortunately this is the easiest part to get right: Be a robot. Don’t make any mistakes.
BE PERFECT IN EVERYTHING YOU DO HERE!!

If you get any errors, learn how to read the error code and fix your error. Google is your friend here. Do NOT continue until you fix your error. Your error will probably be somewhere near the parenthesis numbers (line and character position) in the file. It is almost CERTAINLY your typo causing the error, so look again and fix it.

Step 2. Go back and work through every part of the tutorial again, and this time explain it to your doggie. See how I am doing that in my avatar picture? If you have no dog, explain it to your house plant. If you are unable to explain any part of it, STOP. DO NOT PROCEED. Now go learn how that part works. Read the documentation on the functions involved. Go back to the tutorial and try to figure out WHY they did that. This is the part that takes a LOT of time when you are new. It might take days or weeks to work through a single 5-minute tutorial. Stick with it. You will learn.

Step 2 is the part everybody seems to miss. Without Step 2 you are simply a code-typing monkey and outside of the specific tutorial you did, you will be completely lost. If you want to learn, you MUST do Step 2.

Of course, all this presupposes no errors in the tutorial. For certain tutorial makers (like Unity, Brackeys, Imphenzia, Sebastian Lague) this is usually the case. For some other less-well-known content creators, this is less true. Read the comments on the video: did anyone have issues like you did? If there’s an error, you will NEVER be the first guy to find it.

Beyond that, Step 3, 4, 5 and 6 become easy because you already understand!

Finally, when you have errors…

1 Like
6

Thanks for answer. You absolutely right. After your reply it took 4 days to understand how “coding” works and i solved my static problem.

2 Likes