How to access another project's VS macro $(TargetFileName)? - c++

Question

In Visual Studio 2019 I have two C++ projects contained in the same Solution: ProjectA and ProjectB.
How to define a C/C++ Preprocessor Definition in ProjectB ( let's call it: THE_OTHER_FILE_NAME ), which is equal to the string returned by the VS macro $(TargetFileName) in the ProjectA ?
NOTE: Hardcoding paths in the C/C++ source files is outside the scope of this question.

Answer 1

To access another project's VS macro $(TargetFileName) create the following XML file:
<Project>
<PropertyGroup>
<TargetFileName_Global>__UNDEFINED__</TargetFileName_Global>
<TargetFileName_Global Condition="Exists('$(SolutionDir)TargetFileName.vsmacro')">"$([System.IO.File]::ReadAllText('$(SolutionDir)TargetFileName.vsmacro').trim())"</TargetFileName_Global>
</PropertyGroup>
</Project>
...and name it Directory.Build.props and place it into your Solution Directory (where your *.sln file resides).
Next, in Solution Explorer right-click on the ProjectA's Properties --> Configuration Properties --> Build Events --> Pre-Build Event --> Command Line and set it to:
set /P "_VSdmy=$(TargetFileName.Replace('"','').trim())" <nul> "$(SolutionDir)TargetFileName.vsmacro" ||(call,)
Next, in Solution Explorer right-click on the ProjectB's Properties --> Configuration Properties --> C/C++ --> Preprocessor --> Preprocessor Definitions and add the following code there:
THE_OTHER_FILE_NAME=$(TargetFileName_Global);
Restart Visual Studio.
Now, you can use the THE_OTHER_FILE_NAME preprocessor macro in in ProjectB's *.h, *.c and *.cpp source files at will. This macro will be defined as a string of the ProjectA's target file name.
Note, that the THE_OTHER_FILE_NAME preprocessor macro in ProjectB will have meaningful contents only after you build the ProjectA. Before that happens, this macro will be defined as __UNDEFINED__. After building ProjectA you may have to refresh the Intellisense and the syntax highlighting of this macro in your source files by performing Rescan --> Rescan Solution from the context menu. Forgetting to rescan the solution this way, affects only the Intellisense display - it does not affect the building of any of the projects.
It is possible to do this with any other macro in Visual Studio and with multiple macros in multiple projects as well.
However, this method of passing variables between projects will not work with MsBuild versions earlier than v15.0 (included in Visual Studio starting from version v2017), because older versions ignore the Directory.Build.props file. See the "Updates" section, in this article.
This method will also not work when the MsBuild property ImportDirectoryBuildTargets is set to false.
P.S.
It is also possible to instantly pass a value of an MSBuild variable between projects using the Windows Registry (even through volatile registry keys), however it is not possible to pass it so through an environment variable set by the set command, because environment variables set in this manner do not survive the termination of the process that had set them. ...and each project is built by a separate MsBuild process. The <SetEnv... task has the ability to permanently set an environment variable in the User Profile or the Local Machine through the <SetEnv Target=... attribute, and environment variables set in this manner survive even the reboot, but they are not visible to existing processes (i.e. already running VS) - only to newly spawned processes. Environment variables set by the <SetEnv... task without the Target=... attribute, do not survive the termination of the process that had set them, just like the set command.

Answer 2

You can include file witch you need example
my second project name is p2
path in same folder repo
#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <Windows.h>
#include "../p2/Header.h"
int main(){
print();
system("PAUSE");
}
header file code
#pragma once
#include <stdio.h>
void print() {
printf("Hello\n");
}
And you can cheek this question