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Visual Studio has macros like $(TargetDirectory), $(OutputPath) etc.
In my source code, I want to specify a relative path for the loading of a file from a folder a few levels below the TargetDirectory.
Currently I'm doing this: mLayer = mEngine->AddLayer("D:\\Projects\\abc.osg"); and I want it to be something like mLayer = mEngine->AddLayer(($TargetDirectory)+"..\\..\\abc.osg");

It's just a temporary requirement, so that I can give my code to a person for a small demo, and his TargetDirectory is differently aligned wrt my directories. Is there any way to make use of the Visual Studio macros in source code? (at least I know that System environment variables can be accessed)

Nav
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6 Answers6

13

Go to Project Properties -> Configuration Properties -> C/C++ -> Preprocessor -> Preprocessor Definitions and add the following:

TARGET_DIRECTORY=LR"($(TargetDir))"

This defines a wide string literal named TARGET_DIRECTORY that contains the contents of the $(TargetDir) macro. The important thing here is that this creates a C++ raw string that does not treat backslashes as escape characters. Paths contain backslashes. Using a regular string literal would be incorrect and would even give you compiler errors in some cases.

Important!

If you use a macro that may contain a closing parenthesis followed by double quotation marks )" you must use an additional delimiter, that cannot occur in the macro value, for example:

TARGET_DIRECTORY=LR"|($(TargetDir))|"

In the case of windows file system paths this is not necessary because paths cannot contain double quotation marks.

Tom
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  • Nope. Doesn't work. I tried to cout TARGET_DIRECTORY and got these errors `error C2065: 'LR' : undeclared identifier`, `error C2143: syntax error : missing ';' before 'string'`, `error C2563: mismatch in formal parameter list` – Nav Oct 09 '14 at 11:49
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    Ok, seems like raw strings were introduced with C++11 and are not available in VS 2010. Sorry. It works with VS 2013. – Tom Oct 10 '14 at 03:51
  • Works with VS2017 great. – Sirmabus Dec 14 '19 at 02:24
7

You cannot do this automatically, but you can pass specific MSBuild properties to the preprocessor:

<ItemDefinitionGroup>
  <ClCompile>
    <PreprocessorDefinitions>TARGET_DIRECTORY="$(TargetDirectory)"</PreprocessorDefinitions>
  </ClCompile>
</ItemDefinitionGroup>

This can be configured in the IDE by going to the Project Property Pages dialog, browsing to Configuration Properties -> C/C++ -> Preprocessor Definitions, and adding

TARGET_DIRECTORY="$(TargetDirectory)"

Note that your use of + for string literal concatenation is incorrect: string literals (and C Strings in general) cannot be concatenated using +. Rather, string literals can be concatenated simply by placing them adjacent to each other. For example,

TARGET_DIRECTORY "..\\..\\abc.osg"
James McNellis
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  • I'm not able to use the macro in the code. Compiler says `TARGET_DIRECTORY` is undefined. Besides, when I add `TARGET_DIRECTORY="$(TargetDir)"` to preprocessor definitions, all macros that are defined after it, are ignored by the compiler. Help? – Nav Feb 15 '13 at 06:03
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    This answer doesn't work, because it adds a macro like TARGET_DIRECTORY "C:\abc\". Correct would be TARGET_DIRECTORY "C:\\abc\\". At least my Visual Studio does not auto-escape the backslashes. This leads to compiler errors when the macro is used in code because the last backslash of the target directory changes the meaning of the closing double quotes and the string will therefore not be closed at this position. I pointed this out in my answer which was down voted. – Tom Nov 19 '14 at 08:36
  • Nav: Tom's answer gives the answer to your problem. $(TargetDir) ends with a backslash. So your ending >"< will be escaped. Therefore the definition does not end at that point. – TheTrowser Dec 11 '15 at 12:04
1

Inside Properties -> Configuration Properties -> C/C++ -> Preprocessor -> Preprocessor you can add your directive. 

PROJECT_DIR=R"($(ProjectDir))"

In code you can use it like. 

std::string com = "powershell groovy "PROJECT_DIR"generate_report.groovy " + EXE_DIR;

EXE_DIR is a string in our case.

Dani Konoplya
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I'd suggest making these relative to the application's working directory, or something. Perhaps check out the GetCurrentDirectory function, at http://msdn.microsoft.com/en-us/library/aa364934%28v=vs.85%29.aspx.

Ryan
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-1

Not that I know of but I have an alternative.

Deploy your file as a post build step. In this step you can consume the $(OutDir) macro which represents your binaries drop folder. This should help you place this file at a relative position from your app and use that relative position within your code.

This will also be a lasting solution rather than something done temporarily.

allen
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-1

use TARGET_DIRECTORY=""$(TargetDir)"" instead of TARGET_DIRECTORY="$(TargetDir)" for string macro. (Note double quotes)

Worked for me in VS2005.

Thinkeye
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