Persistent Data

Persistent Data means saving your own data in Cuphead's save file so you can get custom data from the last time you played Cuphead.
For example, Cuphead saves the bosses you've killed, the weapon you are equipping and much more.
In Blender you will use the CustomData class to interact with the custom data.

How to use the class

int slot = 0;
string key = "custom_value";
object value = CustomData.Get(slot, key);
value ??= 0;
int intValue = (int) value;
if (intValue < 10)
    CustomData.Set(slot, key, intValue + 1);
else
    CustomData.Remove(slot, key);

1. In the following example, we get the value of custom_value. If it doesn't exist yet, we assign to it a value of 0.
   
2. After that we get the value as an int and check if it's less than 10, if it is we increment it by 1.
   
3. If it's bigger or equal to 10 we remove it which means that the next time the game runs it will start all over again.
   

To get the current slot the player is in you can use:

int slot = PlayerData.CurrentSaveFileIndex;

To save the game after modifying something you can use:

PlayerData.SaveCurrentFile();