Using file as synth sound sample

Audio Plugins
5 
//        ScopedPointer<AudioFormatReader> audioReader (wavFormat.createReaderFor(new MemoryInputStream (BinaryData::cello_wav,
//                                                      BinaryData::cello_wavSize,
//                                                      false),true));
    
    FileInputStream* cello = new FileInputStream (File ("./cello.wav"));
    if (cello->openedOk()) {
        ScopedPointer<AudioFormatReader> audioReader (wavFormat.createReaderFor (cello,true));
        
        BigInteger allNotes;
        allNotes.setRange (0, 128, true);
        
        synth.clearSounds();
        synth.addSound (new SamplerSound ("demo sound",
                                          *audioReader,
                                          allNotes,
                                          74,   // root midi note
                                          0.1,  // attack time
                                          0.1,  // release time
                                          10.0  // maximum sample length
                                          ));
    }

Hi I’m trying to also use a file as a synth sound sample and I tried implementing what you talked about, but it doesn’t recognize the file.
I also referred to this link: File streaming FileInputStream/FileOutputStream

Please let me know if you can help!