C#•14mo ago

❔ Trying to a initialize a list of objects, but keep getting this error:

I´ve been googling around how I can solve it, but its not working out very well... does someone here know why I get this?

38 Replies

Angius•14mo ago

Uh, this looks like an img element with base-64 image...? Where's the error? Where's the code?

EmelieOP•14mo ago

sorry! here it is

EmelieOP•14mo ago

EmelieOP•14mo ago

The contextual keyword `var' may only appear within a local variable declaration

Angius•14mo ago

Well, yeah, that's true You can use var only for local variables Not for fields or properties

EmelieOP•14mo ago

I dont think I get the difference :/

Angius•14mo ago

$structure

MODiX•14mo ago

namespace Namespace;

[Attribute]
public class Class
{
    public string PublicField;
    private bool _privateField;
    protected double protectedField;    

    public int PublicProperty { get; set; }

    public Class() {} // Constructor

    public void Method(int parameter)
    {
        var localVariable = parameter; 
    } 
}

namespace Namespace;

[Attribute]
public class Class
{
    public string PublicField;
    private bool _privateField;
    protected double protectedField;    

    public int PublicProperty { get; set; }

    public Class() {} // Constructor

    public void Method(int parameter)
    {
        var localVariable = parameter; 
    } 
}

Angius•14mo ago

Fields and properties are class members Locak variables are inside of methods

EmelieOP•14mo ago

oh so I should create a method if I want to use var this way?

Exi•14mo ago

or give it a specific type like Section and dont use var

Angius•14mo ago

Well, do you want sections to be available on class-level or do you want it to be local to a method? That's the question you should be asking

EmelieOP•14mo ago

I want to initialize these objects, fill a combobox with the different sections available, and when the user selects a section, a new window with the specific info on this section should show up if that makes sense giving it a specific type like Section just gives me a bunch of other errors, unfortunately Im doing a WPF app

Exi•14mo ago

List<Sections> sections = new List<Sections> { new Section(), new Section(), }; Did u try that? fill the new section inside like it fits to u

Angius•14mo ago

List<Sections> sections = new()
    {
        new Section(), 
        new Section(),
    };

List<Sections> sections = new()
    {
        new Section(), 
        new Section(),
    };

if you don't want to be repeating the type I didn't want to give out a straight answer but aight, fine

EmelieOP•14mo ago

ok so it works now! thank you. Just trying to understand it a bit more we can´t use var when defining fields and properties of a class?

Exi•14mo ago

imagine if u have fields on class level, they usually need a type when getting initialized and var doesnt provide that

EmelieOP•14mo ago

which is what I was trying to do?

Exi•14mo ago

and they also cant get modifiers like private, public and stuff and that doesnt work out as well

EmelieOP•14mo ago

how come var cant get those modifiers? sorry if thats a stupid question

Angius•14mo ago

It's not that var can't get those modifiers It's that var cannot be used on the class-level

Exi•14mo ago

Mh I'm not a expert on this, I just think it's designed like that, maybe @ZZZZZZZZZZZZZZZZZZZZZZZZZ knows that? never seen that

Angius•14mo ago

Probably some legacy reasons ¯\_(ツ)_/¯ The fact remains, var is only valid for local variables Class-level variables (fields, properties) can use target-type new() at most

EmelieOP•14mo ago

well, guess I dont need to know all of the details anyways! 😄 some things are better to just memorize just one more thing is it correct to say that I have created a fieldvariable which contains objects of the class it defines?

Angius•14mo ago

You created a field, yes It's a list of Sections And contains multiple instances of Section class

EmelieOP•14mo ago

and if I want to add a constructor then I need to leave out this list right?

Angius•14mo ago

What do you mean?

EmelieOP•14mo ago

im not sure 😂 just feeling confused

Exi•14mo ago

what are you trying to do?

EmelieOP•14mo ago

I want to initialize objects of the Section class I am just confused about that its possible to have a field variable in the class, which in turn contains objects of that class Im probably overthinking it

Thinker•14mo ago

It's apparently because it would introduce possible recursion when binding fields. Eg.

private var x = y;
private var y = x;

private var x = y;
private var y = x;

Angius•14mo ago

Oooh, makes sense Well, you... do have a field that contains objects Or do you mean, having a list of Foos inside of the class Foo?

EmelieOP•14mo ago

Yes, that last part😅 about Foo

Angius•14mo ago

Then, yeah, using a constructor would probably be best

EmelieOP•14mo ago

That really confuses me

Angius•14mo ago

And passing the list there Maybe exposing the list as a property, so it can be added to at any time

EmelieOP•14mo ago

that makes sense, I think Anyhow. Thanks once again! Im going to resume to coding 😄

Accord•14mo ago

Was this issue resolved? If so, run /close - otherwise I will mark this as stale and this post will be archived until there is new activity.

Gaming

Programming

❔ Trying to a initialize a list of objects, but keep getting this error: