Null Reference Exception Error. Modified Stats. Need Help.

Question

All right, having trouble with null reference exceptions.....again. So I decided to make an account on Unity in hopes that one of your gifted scripters can help an apprentice such as myself. Here is the error:

NullReferenceException: Object reference not set to an instance of an object ModifiedStats.CalculateModValue () (at Assets/Scripts/Character Classes/ModifiedStats.cs:19) ModifiedStats.Update () (at Assets/Scripts/Character Classes/ModifiedStats.cs:29) BaseCharacterClass.StatsUpdate () (at Assets/Scripts/Character Classes/BaseCharacterClass.cs:193) CharacterGenerator.Start () (at Assets/Scripts/Character Classes/CharacterGenerator.cs:26)

Some scripts to aid your assistance:

 using System.Collections.Generic;
 public class ModifiedStats : BaseStats {
     private List<ModifyingAttribute> _mods; //List of Attributes that Modify Stat
     private int _modValue; //amount added to baseValue of modifiers
     
     public ModifiedStats() {
         _mods = new List<ModifyingAttribute>();
         _modValue = 0;
     }
     
     public void AddModifier( ModifyingAttribute mod) {
         _mods.Add(mod);
     }
     
     private void CalculateModValue() {
         
         if(_mods.Count > 0 )
             foreach (ModifyingAttribute att in _mods) 
                 _modValue += (int)(att.attribute.AdjustedBaseValue * att.ratio);  
         
         
     }
     
     public new int AdjustedBaseValue {
         get{ return _baseValue + _buffValue + _modValue; }
     }
     
     public void Update() {
         CalculateModValue();
     }
 }
 
 public struct ModifyingAttribute {
     public Attribute attribute; 
     public float ratio; 
     
 }

Another one:

 using UnityEngine;
 using System.Collections;
 using System;
 
 public class BaseCharacterClass : MonoBehaviour {
     private string _name;
     private int _level;
     private uint _freeEXP;
     
     private Attribute[] _primaryAttribute;
     private Vital[] _vital;
     private Skill[] _skill; 
     
     public void Awake() {
         _name = string.Empty;
         _level = 0;
         _freeEXP = 0;
         
 
         
         _primaryAttribute = new Attribute[Enum.GetValues(typeof(AttributeName)).Length];
         _vital = new Vital[Enum.GetValues(typeof(VitalName)).Length];
         _skill = new Skill[Enum.GetValues(typeof(SkillName)).Length]; 
         
         SetupVitals();
         SetupPrimaryAttribute();
         SetupSkills();
         
         
         
         
         
     }
 
     
     public string Name {
         get{return _name; }
         set{ _name = value; }
     }
     public int Level {
         get{return _level;}
         set{_level = value;}
     }
     public uint FreeEXP {
         get{return _freeEXP;}
         set{_freeEXP = value;}
     }
     public void AddEXP(uint exp) {
         _freeEXP += exp;
         
     CaluclateLevel();
         
     }
     // add more to this one, incomplete
     //take average of all players skills and assign that as the player level
         
     public void CaluclateLevel() {
     }
     
     public void SetupPrimaryAttribute() {
         for(int cnt = 0; cnt < _primaryAttribute.Length; cnt ++)
             _primaryAttribute[cnt] = new Attribute();
         
     }
     
     public void SetupVitals() {
                 for(int cnt = 0; cnt < _vital.Length; cnt ++)
             _vital[cnt] = new Vital();
         
         SetUpVitalModifiers();
 
 
         
         
     }
     
     public void SetupSkills() {
             for(int cnt = 0; cnt < _skill.Length; cnt ++) 
             _skill[cnt] = new Skill();
         
         SetUpSkillModifiers();
         
 
         
         
     }
     public Attribute GetPrimaryAttribute(int index) {
         return _primaryAttribute[index]; 
     }
     
     public Vital GetVital(int index) {
         return _vital[index];
     }
     public Skill GetSkills(int index) {
         return _skill[index];
     }
     private void SetUpVitalModifiers(){
         //health
         GetVital((int)VitalName.Vitality).AddModifier(new ModifyingAttribute{attribute = GetPrimaryAttribute((int)AttributeName.Physique), ratio = .5f});
         
         //energy
         ModifyingAttribute energyModifier = new ModifyingAttribute();
         energyModifier.attribute = GetPrimaryAttribute((int)AttributeName.Willpower);
         energyModifier.ratio = 1; 
         
         GetVital ((int)VitalName.Energy).AddModifier(energyModifier);
         
         
         
     }
     private void SetUpSkillModifiers(){
         //physique
         ModifyingAttribute SwordsmanshipModifier = new ModifyingAttribute();
         ModifyingAttribute AxemanshipModifier = new ModifyingAttribute();
         ModifyingAttribute BlockModifier = new ModifyingAttribute();
         
         SwordsmanshipModifier.attribute = GetPrimaryAttribute((int)AttributeName.Physique);
         SwordsmanshipModifier.ratio = .33f;
         
         AxemanshipModifier.attribute = GetPrimaryAttribute((int)AttributeName.Physique);
         AxemanshipModifier.ratio = .33f;
         
         BlockModifier.attribute = GetPrimaryAttribute((int)AttributeName.Physique);
         BlockModifier.ratio = .33f;
 
         GetSkills ((int)SkillName.Swordsmanship).AddModifier(SwordsmanshipModifier);
         GetSkills ((int)SkillName.Axemanship).AddModifier(AxemanshipModifier);
         GetSkills ((int)SkillName.Block).AddModifier(BlockModifier);
         
         //finesse
         ModifyingAttribute DaggeryModifier = new ModifyingAttribute();
         ModifyingAttribute MarksmanshipModifier = new ModifyingAttribute();
         ModifyingAttribute TacticsModifier = new ModifyingAttribute();
         
         DaggeryModifier.attribute = GetPrimaryAttribute((int)AttributeName.Finesse);
         DaggeryModifier.ratio = .33f;
         
         MarksmanshipModifier.attribute = GetPrimaryAttribute((int)AttributeName.Finesse);
         MarksmanshipModifier.ratio = .33f;
         
         TacticsModifier.attribute = GetPrimaryAttribute((int)AttributeName.Finesse);
         TacticsModifier.ratio = .33f;
         
         GetSkills ((int)SkillName.Daggery).AddModifier(DaggeryModifier);
         GetSkills ((int)SkillName.Marksmanship).AddModifier(MarksmanshipModifier);
         GetSkills ((int)SkillName.Tactics).AddModifier(TacticsModifier);
         
         //lordcraft
         ModifyingAttribute ChaosModifier = new ModifyingAttribute();
         ModifyingAttribute LightModifier = new ModifyingAttribute();
         
         ChaosModifier.attribute = GetPrimaryAttribute((int)AttributeName.Lordcraft);
         ChaosModifier.ratio = .33f;
         
         LightModifier.attribute = GetPrimaryAttribute ((int)AttributeName.Lordcraft);
         LightModifier.ratio = .33f;
         
         GetSkills ((int)SkillName.Light_Prayers).AddModifier(LightModifier);
         GetSkills ((int)SkillName.Chaos_Prayers).AddModifier(ChaosModifier);
         
         //charisma
         
         ModifyingAttribute CoercionModifier = new ModifyingAttribute();
         ModifyingAttribute MercantileModifier = new ModifyingAttribute();
         
         CoercionModifier.attribute = GetPrimaryAttribute((int)AttributeName.Charisma);
         CoercionModifier.ratio = .33f;
         
         MercantileModifier.attribute = GetPrimaryAttribute((int)AttributeName.Charisma);
         MercantileModifier.ratio = .33f;
         
         GetSkills ((int)SkillName.Coercion).AddModifier(CoercionModifier);
         GetSkills ((int)SkillName.Mercantile).AddModifier(MercantileModifier);
         
         //willpower
         ModifyingAttribute NaturalModifier = new ModifyingAttribute();
         ModifyingAttribute DominateModifier = new ModifyingAttribute();
         
         NaturalModifier.attribute = GetPrimaryAttribute((int)AttributeName.Willpower);
         NaturalModifier.ratio = .33f;
         
         DominateModifier.attribute = GetPrimaryAttribute((int)AttributeName.Willpower);
         DominateModifier.ratio = .33f;
         
         GetSkills ((int)SkillName.Natural_Arts).AddModifier(NaturalModifier);
         GetSkills ((int)SkillName.Domination_Arts).AddModifier(DominateModifier);
         
     
     }
     
     public void StatsUpdate() {
         for(int cnt = 0; cnt < _vital.Length; cnt ++)
             _vital[cnt].Update();
         for(int cnt = 0; cnt < _skill.Length; cnt ++)
             _skill[cnt].Update();
     }
 }

Thank you for all of your help. I am very appreciative.

Answer 1

Answer by SubatomicHero · May 14, 2013 at 07:12 AM

I've got a feeling you need to initialise the values in your struct to some defaults like so:

 public struct ModifyingAttribute 
 {
     public Attribute attribute; 
     public float ratio; 
 
     // See if this works
     ModifyingAttribute(Attribute att = new Attribute(), float r = 0.0f)
     {
         attribute = att;
         ratio = r;
     }  
 }

I know this works in C++, not sure if it works in C#

Add comment · Show 4 · Share

Jase of Dragons · May 16, 2013 at 01:58 AM 0

Share

I tried that, but it didn't work.

Error: Assets/Scripts/Character Classes/$$anonymous$$odifiedStats.cs(37,60): error CS1736: The expression being assigned to optional parameter `att' must be a constant or default value

Really happy you tried to help me. $$anonymous$$eans a lot.

Jase of Dragons · May 16, 2013 at 02:27 AM 0

Share

Thanks for your help, but it does not seem to work. It just turns up another error:

Assets/Scripts/Character Classes/$$anonymous$$odifiedStats.cs(37,59): error CS1736: The expression being assigned to optional parameter `att' must be a constant or default value

Fornoreason1000 · May 16, 2013 at 02:32 AM 0

Share

yea don't use the constrctor optional params need to be compile time constant in C#. try this

 public struct $$anonymous$$odifyingAttribute 
 {
     public Attribute attribute = new Attribute(); 
     public float ratio = 0.0f; 
  
 
  
 }

Jase of Dragons · May 16, 2013 at 03:06 AM 0

Share

when I do that, I get two new errors:

Assets/Scripts/Character Classes/$$anonymous$$odifiedStats.cs(36,26): error CS0573: $$anonymous$$odifyingAttribute.attribute': Structs cannot have instance field initializers Assets/Scripts/Character Classes/$$anonymous$$odifiedStats.cs(37,22): error CS0573: $$anonymous$$odifyingAttribute.ratio': Structs cannot have instance field initializers

I think that you can't arrange it like that in a struct. Idk, but thanks for your help nonetheless.

Null Reference Exception Error. Modified Stats. Need Help.

1 Reply

Your answer

Follow this Question

Related Questions