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How to use CppSharp

I want to use CppSharp to create a C# wrapper for some classes from a C++ library which I intend to use from C# (on a 64 Bit Windows 10 system).
Unfortunately I am absolutely uncertain how to proceed. I cloned CppSharp into my filesystem and built it as described in the 'Getting started' section
https://github.com/mono/CppSharp/blob/main/docs/GettingStarted.md
I also ran all the test successfully.
From what I read in the documentation I was under the impression that to use CppSharp one has to create a C# application (for simplicity a console application), implement an abstract class from CppSharp and execute some commands from CppSharp. From
https://github.com/mono/CppSharp/issues/82
EDIT: Now I use the following code
using CppSharp;
using CppSharp.AST;
using CppSharp.Generators;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace CppSharpTransformer
{
class DllDemoGenerator : ILibrary
{
public static void Main(string[] args)
{
ConsoleDriver.Run(new DllDemoGenerator());
}
void Setup(Driver driver)
{
var options = driver.Options;
options.GeneratorKind = GeneratorKind.CSharp;
var module = options.AddModule("Sample");
module.IncludeDirs.Add(#"C:\Users\Boehm.J\Documents\CppSharpSamples\Sample\include");
module.Headers.Add("Sample.h");
module.LibraryDirs.Add(#"C:\Users\Boehm.J\Documents\CppSharpSamples\Sample\lib");
module.Libraries.Add("Sample.lib");
}
public void SetupPasses(Driver driver) { }
public void Preprocess(Driver driver, ASTContext ctx)
{
}
public void Postprocess(Driver driver, ASTContext ctx)
{
}
void ILibrary.Setup(Driver driver)
{
}
}
}
which is in Program.cs of my Console application I called CppSharpTransformer.
I could make it compile ok (Visual Studio 2022, Console Project with NET 6.0) by adding the following DLLs to my project:
CppSharp.AST.dll
CppSharp.CLI.dll
CppSharp.CppParser.dll
CppSharp.dll
CppSharp.Generator.dll
CppSharp.Parser.Bootstrap.dll
CppSharp.Parser.CLI.dll
CppSharp.Parser.CSharp.dll
CppSharp.Parser.dll
CppSharp.Parser.Gen.dll
CppSharp.Runtime.dll
I added them under "Dependencies (Abhängigkeiten) > Assemblys" and also as files as members of my project.
But I can not execute the application currently, as I get the runtime error:
Could not load file or assembly 'CppSharp.Parser.CLI, Version=0.0.0.0,
Culture=neutral, PublicKeyToken=null'. Das System kann die angegebene
Datei nicht finden.
(The german text says "The system can not find the specified file").
But the dll of this name is, it seems, in place. It occurs in
C:\Users\Boehm.J\Documents\work\CppSharpTransformer\CppSharpTransformer
and in
C:\Users\Boehm.J\Documents\work\CppSharpTransformer\CppSharpTransformer\bin\x64\Release\net6.0

I've just run into the same issue.
Make sure you copy the Ijwhost.dll into your application's output path.
For example like this:
<Target Name="CopyNative" AfterTargets="Build">
<Copy SourceFiles="..\CppSharp\bin\Release_x64\Ijwhost.dll" DestinationFolder="$(OutputPath)" />
</Target>

Using Entity Framework Core 5 (ef-core-5.0) in a Native c++ application

Should it be possible to use ef-core-5.0 in a native c++ application using an c++/cli interop assembly with .net core 5 as the target framework? To experiment with this I've modified the netcore branch of the CppCliMigrationSample (https://github.com/mjrousos/CppCliMigrationSample), changing the from "netcoreapp3.1" to "net5.0" for CppCliInterop and the from "net47;netcoreapp3.1" to "net5.0-windows" for the ManagedLibrary. The sample builds and works as expected with these changes. However, adding the efcore 5 assemblies to ManagedLibrary and trying to a simple query on a scaffolded model fails with the following error:- System.IO.FileNotFoundException: 'Could not load file or assembly 'Microsoft.EntityFrameworkCore, Version=5.0.5.0, Culture=neutral, PublicKeyToken=adb9793829ddae60'. The system cannot find the file specified.'. I figure I need an entry in the app's .config but I'm not sure what it should be. Can anyone help with resolving this?
Following is what I have in my modified ManagedLibrary.csproj:-
ManagedLibrary.csproj
Sample query:
using ManagedLibrary.Context;
using ManagedLibrary.Model;
using System.Linq;
namespace ManagedLibrary
{
public static class Mi2cdbData
{
public static Prjdata GetFirstProject()
{
using (var context = new BaseContext())
{
return context.Prjdata.FirstOrDefault();
}
}
}
}
The following shows how it's being called in CppClinterop.cpp:-
CppClinterop.cpp

c# Register custom dll as processor to Printer++ Config file

I am trying to create a custom printer driver to generate images. For this, I have installed Printer++ which converts print files to postscripts. To convert postscript file to image, I am using ghostscript. Independently both the processes are running fine and I am able to achieve what is required.
But, I need a custom process to generate images in one go. I followed through the Printer++ tutorial but it didn't work.
This is what I have done:
I installed Printer++ and gave the name of the printer driver as- Septane.
In Visual Studio, I created a project- Test.
And the following code in Processor.cs class:
using System;
using System.Net.Mail;
using PrinterPlusPlusSDK;
namespace Test
{
public class Processor : PrinterPlusPlusSDK.IProcessor
{
public PrinterPlusPlusSDK.ProcessResult Process(string key, string psFilename)
{
//Convert PS to Png
psFilename = "b.ps";
MessageBox.Show("Rahul");
ConvertPsToTxt(psFilename);
}
public static string ConvertPsToTxt(string psFilename, string txtFilename)
{
var retVal = string.Empty;
var errorMessage = string.Empty;
var command = "C:\\PrinterPlusPlus\\gs\\gswin64.exe";
var args = string.Format("-dNOPAUSE -dBATCH -dFirstPage=1 -q -r300 -sDEVICE=png256 -sOutputFile=", psFilename, txtFilename);
retVal = Shell.ExecuteShellCommand(command, args, ref errorMessage);
return retVal;
}
}
}
This class inherits from PrinterPlusPlusSDK.IProcessor and implements the PrinterPlusPlusSDK.ProcessResult Process function. I have tested the standalone console project (without using PrinterPlusPlusSDK processor) and that converts ps to png successfully.
Now, as per the tutorial, the dll needs to be deployed to printer++ and registered as a processor. I copied Test.dll to Printer++ installation folder and added an entry to PrinterPlusPlus.exe.config file.
The config entry looks like:
<processors>
<add key="Test"
value="Test.Processor, Septane, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null" />
</processors>
That's it. Now, when I print a file, it gives an error:
Proccessor not found for: Septane
What am I doing wrong?
If anyone has better idea for achieving the same, please let me know. Actually, mine is a commercial product so can't use CutePDF/VerPDf kind options.
Edit: I now know why I was getting error- Processor not found. I renamed my printer to Test and the error disappeared. I have edited my code as well.
For testing, I have added a message box. I expected to get a popup once I give print command. But that is not the case. The ps file is getting generated without an error and that's it. I can't view pop-up message and there is no png converted file. Can someone please help me resolve this issue at least? It doesn't seem to be picking up the dll at all.
Thanks.

Remember The Printer name must be same as the you dll name
If your printer driver name is Septane. Then you must have to create a project name with "Septane". In that case project name "Test" will not work.

Integrating Prolog with C#

I am new to Prolog and C#. When I try to integrate Prolog with C# I found some errors,
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using SbsSW.SwiPlCs;
namespace ConsoleApplication2
{
class Program
{
static void Main(string[] args)
{
// Environment.SetEnvironmentVariable("SWI_HOME_DIR", #"the_PATH_to_boot32.prc"); // or boot64.prc
if (!PlEngine.IsInitialized)
{
String[] param = { "-q" }; // suppressing informational and banner messages
PlEngine.Initialize(param);
PlQuery.PlCall("assert(father(martin, inka))");
PlQuery.PlCall("assert(father(uwe, gloria))");
PlQuery.PlCall("assert(father(uwe, melanie))");
PlQuery.PlCall("assert(father(uwe, ayala))");
using (var q = new PlQuery("father(P, C), atomic_list_concat([P,' is_father_of ',C], L)"))
{
foreach (PlQueryVariables v in q.SolutionVariables)
Console.WriteLine(v["L"].ToString());
Console.WriteLine("all children from uwe:");
q.Variables["P"].Unify("uwe");
foreach (PlQueryVariables v in q.SolutionVariables)
Console.WriteLine(v["C"].ToString());
}
PlEngine.PlCleanup();
Console.WriteLine("finished!");
}
}
}
}
It is not running, Before run this I was add reference SwiPlCs.dll. But it shows error "FileNotFoundException was unhandled, The specified module could not be found. (Exception from HRESULT: 0x8007007E)".
So can anyone help me to fix this error?
I got this coding here

The link you've provided has full explanation of this error:
If libswipl.dll or one of its dependencies could not found you will recive an error like
System.IO.FileNotFoundException: Das angegebene Modul wurde nicht gefunden. (Ausnahme von HRESULT: 0x8007007E)
An other common error is:
SWI-Prolog: [FATAL ERROR:
Could not find system resources]`
Failed to release stacks
To fix this add the SWI_HOME_DIR environment variable as described in SWI-Prolog FAQ FindResources with a statment like this befor calling PlEngine.Initialize.
Environment.SetEnvironmentVariable("SWI_HOME_DIR", #"the_PATH_to_boot32.prc");
This code is commented by default, Uncomment it and provide the correct path to the the_PATH_to_boot32.prc. As described in FAQ:
Solution
On Windows, it suffices to leave libswipl.dll in the installation tree (i.e., do not copy it elsewhere) and add the bin directory of the installation tree to %PATH%.
A cross-platform and robust solution is to use putenv() to put an appropriate path into the environment before calling PL_initialise().
...;
putenv("SWI_HOME_DIR=C:\\Program Files\\swipl");
if ( PL_initialise(argc, argv) )
PL_halt(1);
...
In the final version of your application you link the saved-state to the executable (using swipl-ld or cat (Unix)) and comment the putenv() call.

Could not load file or assembly 'SharpSvn-DB44-20-Win32.dll'

I'm using ASP.NET MVC3, StructureMap and SharpSvn.
Here's the code that I'm using:
public class SvnFileReader : ISvnFileReader
{
private readonly string _svnAddress;
public SvnFileReader(string svnAddress)
{
_svnAddress = svnAddress;
}
public void DownloadFiles(DirectoryInfo destination)
{
using (var svnClient = new SvnClient())
{
// checkout the code to the specified directory
svnClient.CheckOut(new Uri(_svnAddress), destination.FullName);
}
}
}
When I execute this code:
_svnFileReader.DownloadFiles(new System.IO.DirectoryInfo(#"d:\test"));
I get the following error message:
Could not load file or assembly
'file:///D:\Projects\SvnFileReaderDemo\bin\SharpSvn-DB44-20-Win32.dll'
or one of its dependencies. The module
was expected to contain an assembly
manifest.
Any help would be greatly appreciated!

You should exclude the SharpSvn DLLs from StructureMap automatic assembly scanning for dependencies. This is an unmanaged library but because you have configured StructureMap to look for types in all dlls when it tries to load this one it breaks.
UPDATE:
If you are running this code on a x64 bit OS you may try downloading the specific x64 SharpSvn which uses SharpSvn-DB44-20-x64.dll.