Define C# preprocessor from MsBuild
c#, msbuild
Solution
First, you should only define (and test in your code) the symbol, here: `DEMO`
Then, you should conditionally add your symbol to existing symbols (those eventualy defined in project's properties):
In `.csproj` file, after first item `<DefineConstants>` or creating another `<PropertyGroup>` section, add line:
<DefineConstants Condition="'$(DEMO)'=='1'">$(DefineConstants);DEMO</DefineConstants>
PS: this is a tested solution.
Problem
In my `C#` file I want to have a preprocessor condition like this: ``` #if DEMO ShowSplash(); #endif ``` I'm running this command from command line: ``` MSBuild MySolution.sln /p:Configuration=Release /p:Platform="Any CPU" /p:DEMO=1 ``` Then, in `MyProject.csproj` file I have the following: ``` <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' "> <DefineConstants>TRACE;DEMO=$(DEMO)</DefineConstants> </PropertyGroup> ``` But the preprocessor seems to skip my splash code. (I'm aware of the difference between "Any CPU" and "AnyCPU". I never touched that, so I'm quite sure Visual Studio doesn't care about the space.) `DEMO` is not defined? The same construct seems to work in other project types (e.g. `.wixproj`) What am I missing here?