Question

I have three projects under another project of which each contains one namespace. Now among them I need to call a class which is under a namespace in visual studio 2008. Please don’t ask me to add the dependencies to the main project so that I can access the namespace and all the classes in that just like local namespace which I can’t do due to some restrictions. Tell me something like derived class concept so that I can access that class.

The LanguageTable class which I want to call is as follows:

#define GFX_LANGUAGE_MAX 20

namespace gfx_viewer_win32
{
  public ref class LanguageTable 
  {
  public:    
     static Dictionary<String ^, List<String ^>^> ^ language_string_table;
     static array<String ^> ^language_string_id;

     LanguageTable(void)
     {
     }
     ~LanguageTable(void)
     {
     }     
  };
}

The place from where i want to call LanguageTable class is as follows:

#pragma once
using namespace gfx_coder_prj_parser;

namespace Code_generator
{
public ref class CCodeGenerator : CCodeParserMultiLayer
    {
       CCodeGenerator(void)
       {
       }
       ~CCodeGenerator(void)
       {
       }
       /*============I want to call LanguageTable class from here==========*/
    };
}

Answer 1

If you don’t want to add the assembly of LanguageTable class as a reference, you can reach it by System.Reflection. First load the assembly and create an instance of LanguageTable and now you can call methods,access properties of it by searching for by their names like

Assembly ^ langTableAssembly = Assembly::Load("assembly_name" or  binary_data_of_assembly  );
object ^ langTable = langTableAssembly->CreateInstance("gfx_viewer_win32::LanguageTable", ...with_other_params);
Type ^ langTableType = langTable->GetType();
MemberInfo ^ langStringID = langTableType.GetMember("language_string_id")[0];
MethodInfo ^ someMethod = langTableType.GetMethod("method_name");
someMethod->Invoke(langTable, ...other_params);

It is not a good approach though. It depends on the names, any change of the names (via refactoring etc.) you have to fix the code above. And I cannot say, this has the best performance.

Lastly, once loaded, the assembly of LanguageTable will not be unloaded during the execution of program. If you wish to unload it, this is another story called “playing with Appdomains“.

Here and here are some links to begin with.