C#•2w ago

Error with Console and int variables. Syntax error?

Console.ForegroundColor = ConsoleColor.White;
Console.WriteLine("nice! i'm a yellow guy, fyi! " + favouriteColor + " is still very cool, though.");
Console.WriteLine("... \nhey! i've been working on my math recently, how about we give it a go?");
Console.WriteLine("type one number you want for me to add to another, \n make sure it's just a number and nothing else!")

Console.ForegroundColor = ConsoleColor.Blue; 
int num01 = Convert.ToInt32( Console.ReadLine() ); /* < this is a conversion! it always goes at the start of 
you're converting, and you also want to include it's call brackets with it! or, right next to it... */

Console.ForegroundColor = ConsoleColor.White;
Console.WriteLine(num01 + "! great choice! now for what you want to add to it.");

Console.ForegroundColor = ConsoleColor.Blue;
int num02 = Convert.ToInt32( Console.ReadLine() );

Console.ForegroundColor = ConsoleColor.White;
Console.WriteLine("that would be.... " num01 + num02 );

Console.ReadKey(); // < this is the end, though. it can register once you press any key!

// // ^ these however, are Methods/Functions, these are the stuff that actually DO things, not just change them.

Console.ForegroundColor = ConsoleColor.White;
Console.WriteLine("nice! i'm a yellow guy, fyi! " + favouriteColor + " is still very cool, though.");
Console.WriteLine("... \nhey! i've been working on my math recently, how about we give it a go?");
Console.WriteLine("type one number you want for me to add to another, \n make sure it's just a number and nothing else!")

Console.ForegroundColor = ConsoleColor.Blue; 
int num01 = Convert.ToInt32( Console.ReadLine() ); /* < this is a conversion! it always goes at the start of 
you're converting, and you also want to include it's call brackets with it! or, right next to it... */

Console.ForegroundColor = ConsoleColor.White;
Console.WriteLine(num01 + "! great choice! now for what you want to add to it.");

Console.ForegroundColor = ConsoleColor.Blue;
int num02 = Convert.ToInt32( Console.ReadLine() );

Console.ForegroundColor = ConsoleColor.White;
Console.WriteLine("that would be.... " num01 + num02 );

Console.ReadKey(); // < this is the end, though. it can register once you press any key!

// // ^ these however, are Methods/Functions, these are the stuff that actually DO things, not just change them.

76 Replies

retro!OP•2w ago

also ignore the abhorrent amount of comments there are

Ꜳåąɐȁặⱥᴀᴬ•2w ago

well you need a + between "text" and num01 too

retro!OP•2w ago

oh thanks

retro!OP•2w ago

still doesn't explain this though 😢

Ꜳåąɐȁặⱥᴀᴬ•2w ago

there is no ending ; on line above

Thinker•2w ago

What does the error actually say? Also "..." + num1 + num2 won't do what you expect, you need "..." + (num1 + num2)

retro!OP•2w ago

Thinker•2w ago

Is that the greek question mark by any chance

Angius•2w ago

As this_is_pain said, you lack a semicolon Ah Huh Greek question mark is a thing, isn't it lmao

Thinker•2w ago

yep

MODiX•2w ago

Thinker

REPL Result: Failure

Console.WriteLine("foo");

Console.WriteLine("foo");

Exception: CompilationErrorException

- ; expected
- Unexpected character ';'

- ; expected
- Unexpected character ';'

Compile: 409.142ms | Execution: 0.000ms | React with ❌ to remove this embed.

Thinker•2w ago

@retro! Go through all your semicolons and ensure that they are actually ASCII semicolons (;) and not some other character, that seems to be the most reasonable explanation. are you using a greek keyboard layout?

FusedQyou•2w ago

Probably just missing a semicolon

retro!OP•2w ago

uhhh i think it's english?

FusedQyou•2w ago

I can't imagine they somehow got a quirky character in there

retro!OP•2w ago

there are arabic character to it's side, but every time i semicolon i do ";" or something else on accident let me check this

retro!OP•2w ago

the ones that do work still hilights the ones that dont

retro!OP•2w ago

i have no ieda 😭

Thinker•2w ago

Given the slightly offset location of the errors, there might be some invisible character after the semicolon

Angius•2w ago

Copy this: ; and replace those characters with it Just to make sure

retro!OP•2w ago

del just brings the lines below to it pasting this and deleting like... everything after worked!

retro!OP•2w ago

although there are these errors now? i'm gonna check that line on the left

retro!OP•2w ago

okay removing the lines on the left removed the console error

Angius•2w ago

Seems like some weird characters found their way into this code... somehow Did you copy it from somewhere? Could be there were some  s or something

retro!OP•2w ago

nevermind those are still there

retro!OP•2w ago

i don't even know, i was typing and then once i was finished i just noticed that

Angius•2w ago

Try Edit -> Advanced -> View White Space That should show whitespace that's usually invisible

retro!OP•2w ago

yeah it's still this

retro!OP•2w ago

this edit?

Angius•2w ago

Huh, it's not there?

retro!OP•2w ago

is it supposed to be there? i'm following a brackeys tutorial i think that's how you spell brackeys 🤷

Angius•2w ago

Could try this: https://stackoverflow.com/a/73140538/6042255

retro!OP•2w ago

shortcut does this, appaerntly it's command "Edit.ViewWhiteSpace" but i don't know where to enter that

retro!OP•2w ago

-# (there was a typo)

retro!OP•2w ago

found it! it's on by default though

retro!OP•2w ago

so that can't be it

retro!OP•2w ago

so the problem isn't with console, it's with whatever i put there....

retro!OP•2w ago

okay now im just confused WHAT IS TEHRE

retro!OP•2w ago

??????

retro!OP•2w ago

if i retype it goes there? it seems like the red squigle of wrong just appears on that specific space and offest a little to the right BUT i can' move it or tinker with it which means i DID fix

c# Console.ForegroundColor = ConsoleColor.blue;

c# Console.ForegroundColor = ConsoleColor.blue;

but that just put it the problem somewhere else retyping the eltter to the squiggle's right moves it too the right

FusedQyou•2w ago

I think it is just being buggy It will compile assuming the other errors are gone

retro!OP•2w ago

yeah, it just moves wherever

retro!OP•2w ago

it hasn't been compiling (or i guess updating) from the last version since i added this code, from pressing F5 i don't know if the yellow lines matter, i'm going to check those too.

FusedQyou•2w ago

In your case it has to do with nullabillity

retro!OP•2w ago

by the way i'm still on brackey's tutorial and i used .NET Generate Asset for build and debug (or something along with that)

FusedQyou•2w ago

Console.ReadLine is able to return null, although I believe these are obscure cases that won't happen Whatever the case, your variable should be of type string? to indicate they can be null (which is what the question mark indicates)

retro!OP•2w ago

also if i do this again

FusedQyou•2w ago

Additionally, you should create an if-statement in which you check if the value is null. Because if it is and you try to access it, you get a Null Reference Exception. I have no idea what this is I am surprised this tutorial is in VSCode anyway

retro!OP•2w ago

whoops that's irrelivant

FusedQyou•2w ago

I would assume he would use Visual Studio

retro!OP•2w ago

why are there so many VSs 😭 i installed visual community first and sat there for like an hour wondering why i can't get C#

FusedQyou•2w ago

Visual Studio Community? That would be the easiest one even But I would pick the one Brackeys uses

retro!OP•2w ago

guh

retro!OP•2w ago

and guh

FusedQyou•2w ago

For the record, Visual Studio is an "IDE" made specifically for C#. It has the best support. You are using Visual Studio Code, which is more a general text editor that allows the use of pluging very easily. It is also a good pick, but support for C# is less direct and can also be worse.

retro!OP•2w ago

maybe convert.?

FusedQyou•2w ago

What do you mean? I have oractically spoonfed the solution

retro!OP•2w ago

i don't think i understand- my variable is a string, but i still get a nullibility error (i think)

retro!OP•2w ago

this

FusedQyou•2w ago

See if you hover over it it mentions the signature

FusedQyou•2w ago

string? is what it returns, meaning it is either a string or null You are taking in string, meaning just string

retro!OP•2w ago

ohhhh the "?" is part of it i didn't see that that's my bad

FusedQyou•2w ago

So like I said, you need to account for the fact it can be null. Your variable must also use string? Yes This conversion is also bad

retro!OP•2w ago

that's different whoops all it was was one question mark?

FusedQyou•2w ago

Yes But you should fix that part you just send

retro!OP•2w ago

yeah i will

FusedQyou•2w ago

Forget about Convert, never use it. Use $tryparse

MODiX•2w ago

When you don't know if a string is actually a number when handling user input, use int.TryParse (or variants, e.g. double.TryParse)

if (int.TryParse("123", out int number))
{
    var total = number + 1;
    Console.WriteLine(total); // output: 124
}

if (int.TryParse("123", out int number))
{
    var total = number + 1;
    Console.WriteLine(total); // output: 124
}

TryParse returns a bool, where true indicates successful parsing. - Avoid int.Parse if you do not know if the value parsed is definitely a number. - Avoid Convert.ToInt32 entirely, this is an older method and Parse should be preferred where you know the string can be parsed. Read more here

FusedQyou•2w ago

Instead of Convert.ToInt32, use int.Parse. However, your string can be null and it's not guaranteed you input a number. If you try parsing "Hello" it will break So, use int.TryParse instead. See code example above

retro!OP•2w ago

oooh okay

FusedQyou•2w ago

This uses a special out keyword as you can see It basically is another way to return values from a method, but instead via parameters The reason it is done here is because the method itself returns a boolean indicating if it parsed, and the one with out is the actual converted value Hope that makes sense

retro!OP•2w ago

wait so is int.TryParse directly interchangeable with Convert.? or just Parse in general also the random red squigly line of wrong has dissapeard! it was just buggy i think...

FusedQyou•2w ago

No Convert sucks because it does a lot extra under the hood Stuff you might not expect int.Parse would be the alternative but even then it will not parse null That's why you have int.TryParse here, because if it fails you can handle it

retro!OP•2w ago

ahhh that makes sense

Angius•2w ago

Gaming

Programming

Error with Console and int variables. Syntax error?

Did you find this page helpful?