C#•2y ago

❔ can't '-' int

String age = "";
Convert.toInt32(age);
Console.WriteLine (age - 1);
Console.ReadKey();

String age = "";
Convert.toInt32(age);
Console.WriteLine (age - 1);
Console.ReadKey();

Why can't I minus 1 an int? Its a number

53 Replies

Angius•2y ago

This method returns a number It doesn't convert in place After all, age is a string

SoinagieOP•2y ago

But I converted it

Angius•2y ago

And it can only ever remain a string, it can only ever hold a string, it cannot, under any circumstance, hold an integer Convert.ToInt32() RETURNS a number It doesn't change the variable you passed

SoinagieOP•2y ago

Returns to where?

Angius•2y ago

Just... returns To the left of it, let's say Like any method that returns anything

SoinagieOP•2y ago

But I want my string to be an int

Angius•2y ago

age was declared as a string, so it can only ever be a string You need a new variable An int type variable

SoinagieOP•2y ago

Then whats convert even for?

Angius•2y ago

For... converting a string into an int, in this case? I mean, it does what you expect it to

SoinagieOP•2y ago

You said it doesnt convert Just returns

Angius•2y ago

It converts the string into an integer and returns that integer

SoinagieOP•2y ago

Yeah

Angius•2y ago

As I said, C# is statically and strictly typed

SoinagieOP•2y ago

But it doesnt work

Angius•2y ago

A variable cannot change its type It doesn't work because you're using it wrong

SoinagieOP•2y ago

. .

Angius•2y ago

You're not using what the method returns Simple as

SoinagieOP•2y ago

You said 2 opposite things

Angius•2y ago

I didn't? The method doesn't change the type of any variable?

SoinagieOP•2y ago

What method Im just using main

Angius•2y ago

Jesus $helloworld

MODiX•2y ago

Written interactive course https://learn.microsoft.com/en-us/users/dotnet/collections/yz26f8y64n7k07 Videos https://dotnet.microsoft.com/learn/videos

SoinagieOP•2y ago

Nothing else

Angius•2y ago

Start with the basics

SoinagieOP•2y ago

I want my string to be converted to int

MODiX•2y ago

Angius#1586

REPL Result: Success

string text = "420";
int number = Convert.ToInt32(text);
Console.Write(number * 2);

string text = "420";
int number = Convert.ToInt32(text);
Console.Write(number * 2);

Console Output

Compile: 607.266ms | Execution: 34.749ms | React with ❌ to remove this embed.

Angius•2y ago

And, really, go through the linked tutorials You need to know the type system You need to know what methods are

SoinagieOP•2y ago

What type system

MODiX•2y ago

MODiX#0152

Written interactive course https://learn.microsoft.com/en-us/users/dotnet/collections/yz26f8y64n7k07 Videos https://dotnet.microsoft.com/learn/videos

Quoted by

<@!85903769203642368> from #can't '-' int (click here)

React with ❌ to remove this embed.

Angius•2y ago

That types in C# are strict and static and what it means, for example

SoinagieOP•2y ago

I know what methods are And Im using only main I just want my string to be an int but it shows error Why is this int number empty?

Angius•2y ago

Why would it be? It's not empty

SoinagieOP•2y ago

int number =

int number =

Angius•2y ago

It's... not empty?

SoinagieOP•2y ago

So you did convert that string after all

Angius•2y ago

Yes?

SoinagieOP•2y ago

But you said I can't

Angius•2y ago

You can't convert IN PLACE

SoinagieOP•2y ago

What place? Wdym?

Pobiega•2y ago

String age = "";
Convert.toInt32(age);

String age = "";
Convert.toInt32(age);

is NOT THE SAME as

String age = "";
int number = Convert.toInt32(age);

String age = "";
int number = Convert.toInt32(age);

x0rld 👻 🎃•2y ago

you can't change the type of age

Angius•2y ago

Variable text is STILL a string, and it STILL holds the value "420" Variable number is NEW and its type is int The method converted the value and assigned it to a new variable The old variable remains wholly and entirely unchanged

RO // Kronos•2y ago

"wholly and entirely unchanged" very descriptive

SoinagieOP•2y ago

They just said I cant I have to make new variable

x0rld 👻 🎃•2y ago

yes it's normal

SoinagieOP•2y ago

Yes what?

x0rld 👻 🎃•2y ago

age is define as a string you have to create a new variable to have an int

SoinagieOP•2y ago

So I cant change its type like you said