Rust Wiki

Revision Difference

CSharp_Basics#526606

<cat>Dev.Modding</cat> <title>CSharp Basics</title> New to C\#? No clue what this image means? Lets fix that! <upload src="28cbc/8d7dbcdd247fb49.png" size="37896" name="image.png" /> #Labeled Read below to understand what each part of the code means and use this as a reference. Each section below will explain a part of this image. <upload src="28cbc/8d7dbce8d0dcef6.png" size="47652" name="image.png" /> #Comments **What is all that green text scattered around?** Comments are not counted as code and exist purely to explain the purpose or function of code around it. Comments are often written directly above the code they explain, so look right below the green text comments to see what they are explaining. They are written by putting two backslashes `//` at the start of a line. Anything after those `//` will be treated as comments and ignored by the compiler. #Compiler **Hang on, what the heck is a compiler?** A compiler simply takes your code (a text file) and turns it into an executable program that can run on computers. For modding Rust there is a special compiler that can take your code, compile it into a program and run it on the fly without needing to restart or pause the server. # Functions **In CSharp they are called 'methods'** A function is simply a grouping of code that will be ran line by line. Can be executed by writing the name of the function with two parenthesis `()` after it. # Functions / Methods Can be referred to by either name. Functions let us group our code into blocks. This lets use the same code in multiple places and organize by it's purpose. They can be executed by writing the name of the function with two parenthesis `()` after it. ```csharp void MyFunction() { //Here is a comment! Console.WriteLine( "This will be printed in the server console as text!" ); } //Some hook that will be ran by the modding framework void Hook() { //This will call the function 'MyFunction' above MyFunction(); } ``` For the examples below, the function `Hook()` represents the function that will be ran by the modding framework at some point. #What Is Void **Now all I see is void before every function!** In CSharp `void` means nothing. Every function in C# has to return some kind of data. This leads us to a problem: sometimes we don't need any data back from it, as per the example above. That's where `void` comes in: we put the word in front of the function to tell it we want nothing returned. It is a little backwards to think about but makes sense if you think of void as `return nothing`. But what if we actually want to return data... *For the examples below, the function `Hook()` represents a function the modding framework knows about and runs.* # What Is Void **Why do you need to put void before every function!** In CSharp we use `void` to indicate we want the function to return nothing. It is designed this way to help the compiler find the start of the function. If we want it to return something else we put the `Type` in front of the function. But what is a Type? # Types One of the major features of CSharp but present in most languages. **A Type is a grouped block of code and variables.** This allows you to re-use code for multiple things and keep it organized by it's purpose. However, there are two different kinds of types: ___ ## Class The main way you will use `types` to structure and group your code is with `classes`. They can easily be identified by their **Cyan** color when using `Visual Studio`. Examples: * `BaseEntity` * `BasePlayer` * `StorageContainer` * `Monobehaviour` * `Coroutine` Classes are never stored directly: the actual data is stored somewhere in RAM and your variable stores the location of the class's data. ___ ## Null When using classes, `null` represents 'nothing'. Put better explaination here ___ ## Struct You will use them a lot, however it is rare you will create your own `struct`. Examples: * `int` * `float` * `long` * `Vector3` * `Quaternion` * `string` A `struct` will still let you group code and variables together. The main difference is how the data is stored. To begin with you can think of a struct as the same as a class. Later on read the section on <page text="Classes and Structs Explained">Classes_Explained</page> to gain a better understanding. ___ #Return Types Let's say we want to add together some numbers and return the result. In this case, we will put `int` in front of the function (meaning a whole number from -2 Billion -> +2 Billion). This will tell the compiler that we want to return a number after our function runs. Back to functions: let's say we want to add together numbers and return the result as a new number. In this case, we will put `int` in front of the function: which represents a whole number. This will tell the compiler that we want to have a new function and it has to return a number. ```csharp int AddTogetherNumbers() { //This will return a 2 return 1 + 1; } void Hook() { int result = AddTogetherNumbers(); //We have ran the above code and stored the number returned inside a variable called 'result' //Now lets print off the result Console.WriteLine( result ); } ``` # Parameters *Can also be referenced as arguments* Parameters are data or options passed into the parameter. Lets say we want to make a function to count the amount of letters in a player's name ```csharp int CountPlayerName( BasePlayer player ) { //Get's the player's display name and returns the length of the text as an integer number return player.displayName.Length; } ``` #Null Represents 'Nothing'.