C# Default scope resolution

Question

I have inherited a c# class 'Button' (which I can't change) which clashes with the BCL class 'Windows.Forms.Button'. Normally, Id be very happy to go:

MyPackage.MyClass.Button;

But there are a large number or references to this class which is a pain to have to re-type.

Is there any way to get the compiler (linker?) to default to using the customised version of Button over the BCL version?

score 21 · Accepted Answer · answered Oct 06 '08 at 13:22

21

Add this to the top of the file:

using MyButton = MyPackage.MyClass.Button;

Now you can reference your custom button using a distinct name. You may need to do something similar for the stock button if you use that anywhere in the same file.

answered Oct 06 '08 at 13:22

Joel Coehoorn

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This was good to see. I don't think it worked in earlier versions of .NET and I didn't know it was added. – Mark T Oct 06 '08 at 13:31
Works from at least 2.0 on up. – Joel Coehoorn Oct 06 '08 at 13:35
Actually I believe this sort of aliasing has been available from C# 1.0. It's namespace aliases (e.g. alias::typename) which was introduced in C# 2.0. – Jon Skeet Oct 06 '08 at 13:35
This has been available since at least the betas of 1.0. I recall using this syntax in a project I did in .Net 1.0 Beta 2. – Jason Jackson Oct 06 '08 at 13:47

score 4 · Answer 2 · answered Oct 06 '08 at 13:25

if you want to use it by default, replace

using Windows.Forms;

with

using MyPackage.MyClass;

If you do that, you'll need to fully qualify all the buttons from Windows.Forms.

Or, if you want to, you can alias the namespace

using My = MyPackage.MyClass;
//... then
My.Button b = ...

Or alias the button

using MyButton = MyPackage.MyClass.Button;

score 2 · Answer 3 · answered Oct 06 '08 at 13:20

2

You could remove using Windows.Forms; from the top of the code. That would of course mean that you would have to reference all Windows.Forms items specifically.

answered Oct 06 '08 at 13:20

Vincent McNabb

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Nice idea, although given the rest of the classes functionality it leaves me in about the same position as before! – TK. Oct 06 '08 at 13:22

score 0 · Answer 4 · edited Apr 29 '13 at 08:38

0

You can at least make it a small bit less painful/wordy with "using":

using MPMC = MyPackage.MyClass;

then you can say:

MPMC.Button

edited Apr 29 '13 at 08:38

Patrick D'Souza

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answered Oct 06 '08 at 13:24

Mr. Mark

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score 0 · Answer 5 · answered Oct 06 '08 at 13:30

0

It appears that I can do the following:

using Button = MyPackage.MyClass.Button;

works and it preserves all references within the code to Button. Although Im tempted not to go down this route as it is still ambiguious (at least to the reader) which Button is being used.

answered Oct 06 '08 at 13:30

TK.

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Read it again: you can set your own name for the button class that's different from button. – Joel Coehoorn Oct 06 '08 at 13:31
Im aware of that. However, due to the already horrible nature of the code base I was thinking it might be better to stick with the names that are already there e.g. 'Button' rather than another name e.g. 'CustomButton'. Although you could be right is suggesting a unique name. – TK. Oct 06 '08 at 13:36

C# Default scope resolution

5 Answers5