! The story continues, Teo learns how the world functions in the future and finds a way to travel back in time. This is a detailed, deeper C# tutorial, which assumes that you have finished the 

Introduction to while loop

Introduction to methods

Repairing Noname

Introduction to arrays in C#

Lists

Introduction to scopes

Victory is close

Constants in C#

Wonderland

Input validation

Modulo operation

Career raise opportunity

Type conversion

Passing parameters to functions

Infinity

Switch statement

C# test

The truth

C# Intermediate

Learn the while loop; methods; arrays; scopes; constants; var keyword; math library in C#; type casts; ref and out modifiers; switch operator.

Intermediate course from Scratch for Absolute Beginners at CodeEasy Teaching Platform

"Infinity was satisfied with your C# level," Ritchie said to me later that day after I had spoken with Infinity. 
"So... does this mean that I'll be chosen for the Rust project?!" I asked. 
"You're almost there Teo. You'll also need to pass an exam. If you do, then you are The Chosen One. You'd better go get some rest. The exam will take place tomorrow, and I've already said 'goodbye' to you in my mind, so I want you to pass it." 
I nodded and went to the elevator. But instead of going to my floor, I headed to Noname's place in the basement. 
When I got there, the atmosphere was... strange. The lights were flickering, Noname was very quiet, and instructions on his multiple screens just repeated constantly. What was happening?!
"Hi Noname, how are you?" I asked. 
"Hi Teo. I can't find the mistake. There is a mistake, I know, but I can't find it. I-I-I can't find a mistake. I was looking for a mistake but I-I-I c-c-couldn't find it. No mistake, but there is one. Can't find a mistake..." Noname trailed off. 
"Okay, okay... I get it. You're looking for a mistake, but you've had no luck in finding it. I'm sorry to see you in this state, how can I help you?" I asked, concerned. 
"I have this method, but it doesn't change parameters that I pass to it. I don't understand why. Please, look for an article in the local network, maybe you'll find something useful about passing parameters to methods." Noname begged me. 
"Sure Noname, I will do! I'll come back in a little while." I tried to speak optimistically, as I was definitely the only optimist in this room. Come to think of it, I was the only 

 in the room, and I'm not sure one can apply 'optimistic' to a machine. Still, I knew I had to try to understand what was so tricky about passing parameters to methods... 


In the next to no time, I found an article on the local network about passing parameters to methods. I began to read: 
"Let's take a simple exercise of calling a method, 

The article continued, "You probably expected the output to be": 
int inside the method call: 9 
int after the method call: 9 

"The trick here is in 

 method. In the above example, the parameter exampleInt was 

was therefore working with a copy of the exampleInt variable

 returned, the value of exampleInt remained the same. 

This type of parameter passing (when the callee 

In this case, if the callee modifies the parameter variable, the effect 

As you can imagine, there is another type of parameter passing; 

When a parameter variable is passed by reference, the caller, and the callee use and change the same variable.

 If the callee modifies this variable, the effect 

 This means that almost all types that you know, like 

, etc, are passed in this way. If you, as a programmer, want to pass a built-in type by reference, you should use the keywords 

You should put them before the variable name when you call a method and in the method's parameters list. Here is an example": 

"As you can see in the example, when we passed the parameters by reference, the 

 method was working with the same variable as the 

 changed and the output changed too": 
int inside the method call: 9 
int after the method call: 9 

 parameter, is required to have a value assigned to this parameter. When the method takes a 

 parameter, it can leave its value unassigned.

The article continued, "And finally, out in the wild, when you are going to write real programs that are important, please, remember these simple rules": 

 where possible. Use function return values instead.

 if you want to use the value of the variable inside the method and may need to change it.

 if you want to return additional values from the function. 

"All types that are passed by value, by default, are called 

. Types that are passed by reference by default, are called 

You can also remember the difference, by remembering that 

The rest are value types. 
Look at this comparison diagram for 

The article finished with an example. "Here's an example, where we pass an 

I really liked the article. It was clear and easy to understand. After reading everything, I ran to the basement to fix Noname's module. What I found there wasn't the easiest task in the world... but I knew I'd fix it! 


Learn different ways of passing parameters to a method in C#. C# pass by reference, by value. Learn how to apply keywords REF and OUT in C#.