Application Dynamically Links to a DLL Using a Class (85282)

SUMMARY

DYNDLL is a file in the Microsoft Download Center that demonstrates using a class, called CDynDLL, to dynamically link to a DLL. The CDynDLL constructor loads the library and retrieves pointers to each function exported by the DLL. The CDynDLL destructor frees the library. The member functions of the CDynDLL class correspond to the functions exported by the DLL.

MORE INFORMATION

The following file is available for download from the Microsoft Download Center:

Rdo1test.exe

For additional information about how to download Microsoft Support files, click the following article number to view the article in the Microsoft Knowledge Base:

119591 How to Obtain Microsoft Support Files from Online Services

Microsoft scanned this file for viruses. Microsoft used the most current virus-detection software that was available on the date that the file was posted. The file is stored on security-enhanced servers that help to prevent any unauthorized changes to the file. The traditional methods an application uses to dynamically link to a dynamic-link library (DLL) in the Windows environment, using the LoadLibrary() and FreeLibrary() functions, can be awkward. The application is required to call GetProcAddress() for each DLL function the application links to, and the application is then required to store the returned address in an array. The source code of the application must also contain a prototype for each called function or the programmer must cast each function parameter to the required type.

The object-oriented techniques of Microsoft C/C++ version 7.0 can be applied to ease the process of dynamically linking with a DLL. An application can define a class that links to the DLL and contains pointers to each of the exported functions. Member functions of the class correspond to the exported functions in the DLL.