I want to play a MP3 file, and I use DirectShow to play. But I have a problem!! /////////////My Function//////////////// //Suppose initiation is OK!! void playMP3( string fileName ) { pGraphBuilder->RenderFile( fileName.data(), NULL ); ^^^^^^^^^^^^^^^^ //I want that I can input a fileName to execute, //but I only play with RenderFile( L"c:\\test.mp3", NULL ); pMediaContorl->Run(); } ////////////////////////////////////////// So how can I do for this??