.NET Framework - Class ... Why is this not working?

Asked By shapper

25-Jun-08 09:13 PM

Hello,

I have the following classes:

namespace MyApp.Models {
public class Tie {
public Count Count { get; set; }
public Tie() {
this.Count = new Count();
}
}
}
namespace MyApp.Models
{
public class Count
{
public int File { get; set; }
public int Professor { get; set; }
}
}

However, when I access the Tie class in my code the only think Visual
Studio recognizes is:
Tie.Tie.Tie ...

Why can't I access Tie.Count ?

The Tie method inside the Tie class is only a constructor to
initialize the Count property.

Am I doing something wrong?

I have been using VB.NET for a long time and C# just recently so I am
still getting familiar with it.

Thanks,
Miguel

25-Jun-08 09:13 PM

try instantiating a Tie class then try to access;

Tie tie = new Tie();
tie.Count

25-Jun-08 09:13 PM

Count is an instance property - so you should be able to do:

Tie someTie =3D new Tie();
Count count =3D someTie.Count;

But you cannot do:

Count count =3D Tie.Count;

Jon

25-Jun-08 11:38 AM

Since this is newer to you, I'm gonna try to post what I think you're after.
I"m not sure though.

I renamed one thing to "TheCount" so we can avoid ambiguity in the
discussion.



Tie t1 = new Tie();

Console.WriteLine(t1.TheCount.File);

Console.WriteLine(t1.TheCount.Professor);






public class Tie

{

private Count _count1 = null;

public Count TheCount

{

get

{

return _count1;

}

set

{

_count1 = value;

}

}



public Tie()

{

this.TheCount = new Count();

}

}



public class Count

{

private int _file = 0;

private int _prof = 0;

public int File

{

get

{

return _file;

}

set

{

_file = value;

}

}



public int Professor

{

get

{

return _prof;

}

set

{

_prof = value;

}

}





}

25-Jun-08 09:13 PM

I am trying to do the following:

data.TagPapers =3D (from t in
database.Tags
select new TagPaper {
Tag =3D t,
Tie.Count.File =3D
t.FileTag.Count
}).ToList

Where TagPapers is a List of TagPaper which is a class with 2
properties: Tag and Tie.

Shouldn't this be working?

It is not working on Tie.Count.File

I have no idea what is wrong. It seems right to me.

Any idea?

Thanks,
Miguel

25-Jun-08 09:13 PM

I am trying to do the following:

data.TagPapers =3D (from t in
database.Tags
select new TagPaper {
Tag =3D t,
Tie.Count.File =3D
t.FileTag.Count
}).ToList

Where TagPapers is a List of TagPaper which is a class with 2
properties: Tag and Tie.

Shouldn't this be working?

It is not working on Tie.Count.File

I have no idea what is wrong. It seems right to me.

Any idea?

Thanks,
Miguel

25-Jun-08 09:13 PM

I am trying to do the following:

data.TagPapers =3D (from t in
database.Tags
select new TagPaper {
Tag =3D t,
Tie.Count.File =3D
t.FileTag.Count
}).ToList

Where TagPapers is a List of TagPaper which is a class with 2
properties: Tag and Tie.

Shouldn't this be working?

It is not working on Tie.Count.File

I have no idea what is wrong. It seems right to me.

Any idea?

Thanks,
Miguel

25-Jun-08 09:13 PM

t new TagPaper {
ag =3D t,
ie.Count.File =3D
ist

Sloan,

But since, I think, NET 3.0 there are automatic properties so you
don't need all those variables:
http://weblogs.asp.net/scottgu/archive/2007/03/08/new-c-orcas-language-feat=
ures-automatic-properties-object-initializers-and-collection-initializers.a=
spx

That was what I was doing.

Thanks,
Miguel

25-Jun-08 09:13 PM

t new TagPaper {
ag =3D t,
ie.Count.File =3D
ist

Sloan,

But since, I think, NET 3.0 there are automatic properties so you
don't need all those variables:
http://weblogs.asp.net/scottgu/archive/2007/03/08/new-c-orcas-language-feat=
ures-automatic-properties-object-initializers-and-collection-initializers.a=
spx

That was what I was doing.

Thanks,
Miguel

25-Jun-08 09:13 PM

Careful of terminology - automatic properties are part of C# 3.0,
not .NET 3.0.
See http://csharpindepth.com/Articles/Chapter1/Versions.aspx

Jon

25-Jun-08 09:13 PM

No, it shouldn't. (It would have been helpful to explain that you were
trying to use an object initializer in your first post, btw - this is
where short but complete examples come in very handy.)

You can do:

select new TagPaper { Tag = t, Tie = { Count = { File =
t.FileTag.Count } } }

That's the proper syntax for setting properties on embedded objects.

Jon

25-Jun-08 09:13 PM

007/03/08/new-c-orcas-languag...

I think I got it ... I changed my LINQ procedure to:

TagPaper paper =3D (from t in database.Tags
where t.TagID =3D=3D id
select new TagPaper {
Tag =3D t,
new Tie {
new Count {
File =3D t.FileTag.Count
}
}
}).SingleOrDefault();

Now it does not give me any error ...

Jon, I will read what you sent me ... Ok, C# 3.0.

25-Jun-08 09:13 PM

/2007/03/08/new-c-orcas-languag...
leTag.Count

Thanks Jon.

Yes I know but I though the problem was with my classes ... I am just
moving from VB.NET to C# since I started to use MVC ...

Thank you for the help!
Miguel

25-Jun-08 09:13 PM

It should. It certainly does in my test program.

It should be "Tie = {" rather than "new Tie {" and the same for Count.
(You could equally do "Tie = new Tie {" which is subtly different,
setting the Tie property rather than merely setting properties within
the existing value.)

Jon

25-Jun-08 12:59 PM

Ok, I didn't realize you were there yet.

And I'm a little behind in the 3.5 (framework).





Sloan,

But since, I think, NET 3.0 there are automatic properties so you
don't need all those variables:
http://weblogs.asp.net/scottgu/archive/2007/03/08/new-c-orcas-language-features-automatic-properties-object-initializers-and-collection-initializers.aspx

That was what I was doing.

Thanks,
Miguel

25-Jun-08 09:13 PM

FileTag.Count

In fact it must be:
TagPaper paper =3D (from t in database.Tags
where t.TagID =3D=3D id
select new TagPaper {
Tag =3D t,
Tie =3D new Tie { Count =3D new Count{ File =3D
t.FileTag.Count } }
}).SingleOrDefault();

If I don't use new Tie:

TagPaper paper =3D (from t in database.Tags
where t.TagID =3D=3D id
select new TagPaper {
Tag =3D t,
Tie =3D { Count =3D { File =3D t.FileTag.Count } =
}
}).SingleOrDefault();

I get the error: System.InvalidOperationException: Unhandled binding
type: MemberBinding

So I think there is no way around it ... must use new.

Thanks,
Miguel

25-Jun-08 02:37 PM

Well, that depends on the context.


If you're using LINQ to SQL, it looks like it. That would be fine for
LINQ to Objects - it's valid C#, just not a pattern LINQ to SQL
recognises.

--
Jon Skeet - <skeet@pobox.com>
Web site: http://www.pobox.com/~skeet
Blog: http://www.msmvps.com/jon_skeet
C# in Depth: http://csharpindepth.com