The best way to save game data in Unity that's secure & platfrom independent

Question

I am looking for a way to save the users progress for my game, I am looking for something that can't be tampered with/modified. I would like to have to be able to be platform independent. And I would like it to be stored within the game files to the user can transfer their data to different computers (with a flash drive or something). (Correct me if I'm wrong in any area) But I believe because I need to to be secure and platform independent that removes player prefs from the equation. I know there is a way to save data by encrypting it with Binary, but I don't know how that works and if the user could transfer the data from computer to computer. Is there a better way of saving data? Is encrypting is through Binary the way to go? If so how would I do it? Thank you :) If you have any questions feel free to ask.

Edit: I understand nothing is completely secure, I'm looking for something that can stop the average user from going into a file, changing a float, and having tons and tons of money in game.

Answer 1

The first way to save data in unity is use PlayerPrefs, using for example:

PlayerPrefs.SetString("key","value");
PlayerPrefs.SetFloat("key",0.0f);
PlayerPrefs.SetInt("key",0);
PlayerPrefs.Save();

and for get, you only need

PlayerPrefs.GetString("key","default");

The second way and the way that permit you stored in a independent file is use serialization, my prefer way is a use the json file for it.

1) make a class that will store the data (not necessarily it need extends of monobehaviour:

[System.Serializable]
public class DataStorer {
  public data1:String = "default value";
  public data2:Int = 4;
  public data3:bool = true;
  ....
}

and store it in another class with

DataStorer dataStorer  = new DataStorer();
.... // some change in his data
string json = JsonUtility.ToJson(this, true);//true for you can read the file
path = Path.Combine(Application.persistantDataPath, "saved files", "data.json");
File.WriteAllText(path, json);

and for read the data

string json= File.ReadAllText(path);
DataStorer dataStorer = new DataStorer();
JsonUtility.FromJsonOverwrite(json, dataStorer);

and now you dateStorer is loaded with the data in your json file.