C# Code Style Guide For Game Creator

Introduction
Seeing how many programming languages there are and how many companies use their own coding conventions, it is favorable for the developers to have a certain standard they can refer to. The same goes for the Unity assetstore, where a developer of an asset has written code that may be or may not be readable. This code style guide is designed to give you an overview of how code may be structured within the Game Creator eco system. It is based on these two coding style guides: 
​sourceformat.com - C# Code Style Guide​
​microsoft.com - C# Coding Conventions​
The target Unity version for this code style guide is Unity 2020.3 LTS with support for the C# 8 language features. 
Reference: https://docs.unity3d.com/2020.3/Documentation/Manual/CSharpCompiler.html​
Organization
Source Files
One class per file (except classes in a class)
The class name must match the file name (e.g. class name is Test then the file name is Test.cs)
Ordering
The structure of a script is as follows: 
using statements
namespace statements
Class and Interface declarations
Layout
Indentation is four spaces long (equals one tab)
Only one statement per line
Only one declaration per line
If continuation lines are not indented automatically, indent them one tab stop (four spaces)
Add at least one blank line between method definitions and property definitions
Wrapping lines
When an expression does not fit on a single line, follow these breaking rules: 
Break after an operator
Break after a comma
Indent once after a break (see 4th point in Layout)
Comments
Place the comment on a separate line, not at the end of a line of code
Begin comment text with an uppercase letter
End comment text with a period
Insert one space between the comment delimiter (//) and the comment text, as shown in the following example:
// The following declaration creates a query. It does not run
// the query.
Language
Declaration security
Declaration
Notes
Fields
First protected, then public, then private
Properties
First protected, then public, then private
Methods
First protected, then public, then private
In order to not need to change a script of a module of Game Creator, the fields etc. have the protected security flag as default, so they can be accessed and changed by scripts that derive of the other. 
Method declaration
Methods are generally written with the virtual keyword, so they can be overridden by other scripts. 
// Script 1.
public virtual float GetFloat() => floatValue;
​
// Script 2.
public override float GetFloat() => floatValue2;
Naming
Identifier Type
Naming Rules
Examples
Namespaces
A noun in Pascal case. When the word consists of two or less characters, it is written in capital case. Avoid acronyms and abbreviations when possible. 
GameCreator.Core;
UnityEngine.UI;
Classes
A noun written in Pascal case, avoid acronyms and abbreviations when possible. 
class ActionHit;
class ConditionX;             
Interfaces
A word in Pascal case, starting with the letter "I".
interface IAction;
Methods
Active verb/noun forms written in Pascal case.
GetLetter();
UpdateHierarchy();
Instance Fields
Meaningful names written in camel case. Underscores should not be used for private or protected variables. 
protected string name;
public int age;
Enum Types / Values
Words written in Pascal case. Do not use the Enum suffix on Enum type names. When more than two values, it is recommended to write each value on its own line. 
enum State {On, Off};
enum World
{
    Curved,
    Round,
    AroundTheCorner      
}
Events
Written in Pascal case. 
EventActivation onActivate;
Attributes
Custom attributes are in Pascal case and have the suffix "Attribute". 
SingleSkillAttribute;
Properties
Properties are written in Pascal case. They should directly reflect the underlying attribute (field). 
public string Name;
public int Age;
Local Variables
These are written in camel case. Avoid using acronyms and abbreviations. 
int age = 6;
Order order = new Order();
Constants
Constants are written in Pascal Case, but may also be written in all uppercase. 
const int NumDaysInWeek = 4;
const int NUM_DAYS_IN_WEEK = 4
Strings
​String interpolation should be used to concatenate string:
string displayName = quot;{nameList[n].LastName}, {nameList[n].FirstName}";
Local Variables
​Implicit typing for local variables may be used when the type of the variable is obvious from the right side of the assignment or when the precise type is not important
var var1 = "This is clearly a string.";
var var2 = 27;
​var should not be used when the type is not apparent from the right side of the assignment
int var3 = Convert.ToInt32(Console.ReadLine());
int var4 = ExampleClass.ResultSoFar();
Do not rely on the variable name to specify the type of the variable, it might not be correct
Arrays
Use the concise syntax when you initialize arrays on the declaration line:
// Preferred syntax. Note that you cannot use var here instead of string[].
string[] vowels1 = { "a", "e", "i", "o", "u" };
​
// If you use explicit instantiation, you can use var.
var vowels2 = new string[] { "a", "e", "i", "o", "u" };
​
// If you specify an array size, you must initialize the elements one at a time.
var vowels3 = new string[5];
vowels3[0] = "a";
vowels3[1] = "e";
Conditional logical operators
Use && as well as || for comparisons in order to avoid exceptions and increased performance due to skipped unnecessary comparisons. 
Null propagation
Unity overrides the null comparison operator for Unity objects and therefore the C# null propagation feature is incompatible.
public GameObject test = null;
​
// Set in the inspector.
public Transform test2;
​
private void Update()
{
    // Should not be done.
    test?.transform = test2;
    
    // Correct comparison.
    if (test != null)
    {
        test.transform = test2;
    }
    
    // Shortened version is also possible.
    if (test != null) test.transform = test2;
}
​