#define on multiple files

  • Thread starter Thread starter David Young
  • Start date Start date
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David Young

Hello all,

I'm quite new to C# (< 6 months) but really love it and is my language of
choice ..... but I have one question I've not been able to find out .....

In C++ a #define label in one file can be referanced in other *.cpp files,
however in C# if I have say #define SPEED it only refers to the class(es)
in that *.cs file.

Is there anyway to have one #define label work with multiple *.cs files?

Thank you for your time,

David
 
Hi,

Define it in the project level, in the project properties / Configuration
properties / build / Conditional compilation constants

One problem I have faced is that you cannot define a symbol solution wide, I
would like to have that feature implemented sometimes in the future.


Cheers,
 
Cheers Ignacio, that's the trick!!!!

David

Ignacio Machin ( .NET/ C# MVP ) said:
Hi,

Define it in the project level, in the project properties / Configuration
properties / build / Conditional compilation constants

One problem I have faced is that you cannot define a symbol solution wide, I
would like to have that feature implemented sometimes in the future.


Cheers,
Click to expand...
 
Why do you want a #define at all? #defines cause as many problems as
they solve, which is why their functionality is reduced in C# (and they are
working on reducing it in C++)

My guess is that you have some code like the following:

#if SPEED
// fast way of doing something
#else
// slow/careful way of doing that thing.
#endif

IF so, then you should note that if you have a class like:

class Configuration
{
public const bool Speed = true;
}

then you can write code like this:

if (Configuration.Speed)
{
// fast way of doing something
}
else
{
// slow/careful way of doing that thing.
}


This will be compiled PRECISELY the way the top code way, with code
being generated just the "true" portion of the if(). (This is a requirement
of the C# language)


--
Truth,
James Curran
[erstwhile VC++ MVP]

Home: www.noveltheory.com Work: www.njtheater.com
Blog: www.honestillusion.com Day Job: www.partsearch.com
 
Fully agree with you, but I need a "global" switch where I can change in one
place rather than going through many *.cs files setting the bool flag on
each class (and possibly missing the odd one!)

David


James Curran said:
Why do you want a #define at all? #defines cause as many problems as
they solve, which is why their functionality is reduced in C# (and they are
working on reducing it in C++)

My guess is that you have some code like the following:

#if SPEED
// fast way of doing something
#else
// slow/careful way of doing that thing.
#endif

IF so, then you should note that if you have a class like:

class Configuration
{
public const bool Speed = true;
}

then you can write code like this:

if (Configuration.Speed)
{
// fast way of doing something
}
else
{
// slow/careful way of doing that thing.
}


This will be compiled PRECISELY the way the top code way, with code
being generated just the "true" portion of the if(). (This is a requirement
of the C# language)


--
Truth,
James Curran
[erstwhile VC++ MVP]

Home: www.noveltheory.com Work: www.njtheater.com
Blog: www.honestillusion.com Day Job: www.partsearch.com

I'm quite new to C# (< 6 months) but really love it and is my language of
choice ..... but I have one question I've not been able to find out ......

In C++ a #define label in one file can be referanced in other *.cpp files,
however in C# if I have say #define SPEED it only refers to the class(es)
in that *.cs file.

Is there anyway to have one #define label work with multiple *.cs files?
Click to expand...
Click to expand...
 
Look again at my code.

You change it once (in the Configuration class ), and it is global
throughout your code.

--
--
Truth,
James Curran
[erstwhile VC++ MVP]

Home: www.noveltheory.com Work: www.njtheater.com
Blog: www.honestillusion.com Day Job: www.partsearch.com

David Young said:
Fully agree with you, but I need a "global" switch where I can change in one
place rather than going through many *.cs files setting the bool flag on
each class (and possibly missing the odd one!)

David


James Curran said:
Why do you want a #define at all? #defines cause as many problems as
they solve, which is why their functionality is reduced in C# (and they are
working on reducing it in C++)

My guess is that you have some code like the following:

#if SPEED
// fast way of doing something
#else
// slow/careful way of doing that thing.
#endif

IF so, then you should note that if you have a class like:

class Configuration
{
public const bool Speed = true;
}

then you can write code like this:

if (Configuration.Speed)
{
// fast way of doing something
}
else
{
// slow/careful way of doing that thing.
}


This will be compiled PRECISELY the way the top code way, with code
being generated just the "true" portion of the if(). (This is a requirement
of the C# language)


--
Truth,
James Curran
[erstwhile VC++ MVP]

Home: www.noveltheory.com Work: www.njtheater.com
Blog: www.honestillusion.com Day Job: www.partsearch.com

I'm quite new to C# (< 6 months) but really love it and is my language of
choice ..... but I have one question I've not been able to find out .....

In C++ a #define label in one file can be referanced in other *.cpp files,
however in C# if I have say #define SPEED it only refers to the class(es)
in that *.cs file.

Is there anyway to have one #define label work with multiple *.cs
Click to expand...
files?
Click to expand...
Click to expand...
 
This will be compiled PRECISELY the way the top code way, with code
being generated just the "true" portion of the if(). (This is a requirement
of the C# language)
Click to expand...

It's not quite the same though - the code which doesn't actually get
put in the assembly still needs to be valid C#, whereas with a #if it
doesn't. I agree that most of the time that isn't a problem, but in
some cases it might be (for instance, if you want to be able to
conditionally compile against code which doesn't exist in a certain
configuration).

It also doesn't work for things like #if-ing attributes, which can be
handy sometimes.
 
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