Question

我正在尝试从DLL中导出字符串，该字符串来自DLL中包含的库。我的DLL包含CMMCore.lib库，并且CMMCore类具有getDeviceAdapterNames()函数。该函数返回一个字符串。

我到libary（.lib）的C ++代码是：

#include "PluginManager.h"
...
std::vector<std::string> CMMCore::getDeviceAdapterNames() throw (CMMError)
{
      return pluginManager_->GetAvailableDeviceAdapters();
}
...

它从PluginManager.cpp调用另一个函数：

CPluginManager::GetAvailableDeviceAdapters()
{
   std::vector<std::string> searchPaths = GetActualSearchPaths();

   std::vector<std::string> modules;

   for (std::vector<std::string>::const_iterator it = searchPaths.begin(), end =     searchPaths.end(); it != end; ++it)
      GetModules(modules, it->c_str());

   std::set<std::string> moduleSet;
   for (std::vector<std::string>::const_iterator it = modules.begin(), end =     modules.end(); it != end; ++it) {
      if (moduleSet.count(*it)) {
         std::string msg("Duplicate libraries found with name \"" + *it + "\"");
         throw CMMError(msg.c_str(), DEVICE_DUPLICATE_LIBRARY);
      }
   }
   return modules;
}

我的DLL代码是：

#include <MMCore.h>
#include <boost/shared_ptr.hpp>
#include <boost/weak_ptr.hpp>
#include <vector>
using namespace std;
EXPORT void getDevice_dll(char* input_string) 
{   
    CMMCore * v = new CMMCore;
    v->CMMCore::getDeviceAdapterNames();
    memcpy(input_string, v, 20);
}

我想将CMMCore :: getDeviceAdapterNames中的字符串放入*（input_string），但是不起作用。

是否可以将CMMCore::getDeviceAdapterNames中的字符串放置到我自己命名的指针或变量值上？

Answer 1

当CMMCore::getDeviceAdapterNames返回一个字符串向量时，代码应为：

    //max_input_string_size <- size of the input buffer.
    //return the number of device found and saved in input_string, -1 if error.
    EXPORT int getDevice_dll(char* input_string, int max_input_string_size )
    {
            std::vector<std::string> modules;
            try {
                    //if getDeviceAdapterNames was declared as a static member function
                    modules = CMMCore::getDeviceAdapterNames();

                    //if non static member function:
                    modules = CMMCore().getDeviceAdapterNames();

            }catch( CMMError &e ){
                    //handle the error here
                    return -1; //error DEVICE_DUPLICATE_LIBRARY
            }

            string strOutput;

            //change this if your application use other separator(e.g : "\r\n" or "," or "|")
            string strSeparator(";");
            for(int i = 0; i < modules.size(); i++ ){
                    strOutput += modules[i] + strSeparator;
            }
            strncpy( input_string, strOutput.c_str(), max_input_string_size );
            return modules.size();

    }

从库类函数导出DLL字符串

1 个答案: