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Multiple Classes in a Visual Basic Component

To create the component for this example, see the first few steps of the Multiple Classes in a .NET Component. Then create a Microsoft® Visual Basic® application as follows:

  1. Review the sample application for this example in matlabroot\toolbox\dotnetbuilder\Examples\VSVersion\NET\SpectraExample\SpectraVBApp\SpectraApp.vb.

    The program listing is shown here.


    The program does the following:

    • Constructs an input array with values representing a random signal with two sinusoids at 15 and 40 Hz embedded inside of it

    • Uses MWNumericArray to handle data conversion


      For information about these data conversion classes, see the MATLAB MWArray Class Library Reference, available in the matlabroot\help\dotnetbuilder\MWArrayAPI folder, where matlabroot represents your MATLAB® installation folder

    • Instantiates a SignalAnalyzer object

    • Calls the computefft method, which computes the FFT, frequency, and the spectral density

    • Instantiates a Plotter object

    • Calls the plotfft method, which plots the data

    • Uses a try/catch block to handle exceptions

    The following statements

    Dim data As MWNumericArray = New MWNumericArray_
        (MWArrayComplexity.Real, MWNumericType.Double, numSamples)
    Dim resultArray As MWNumericArray = New MWNumericArray_
         MWNumericType.Double, numElements)

    show how to use the MWArray class library to construct the necessary data types.

    The following statement

    Dim signalAnalyzer As SignalAnalyzer = New SignalAnalyzer

    creates an instance of the class SignalAnalyzer, and the following statement

    Dim argsOut() As MWArray = 
        signalAnalyzer.computefft(3, data, 

    calls the method computefft and request three outputs.

  2. Build the SpectraApp application using Visual Studio® .NET.

    1. The SpectraVBApp folder contains a Visual Studio .NET project file for this example. Open the project in Visual Studio .NET by double-clicking SpectraVBApp.vbproj in Windows® Explorer. You can also open it from the desktop by right-clicking SpectraVBApp.vbproj > Open Outside MATLAB.

    2. Add a reference to the MWArray component, which is matlabroot\toolbox\dotnetbuilder\bin\architecture\framework_version\mwarray.dll.

    3. If necessary, add (or update the location of) a reference to the SpectraComp component which you built in a previous step. (The component, SpectraComp.dll, is in the \SpectraExample\SpectraComp\x86\V2.0\Debug\distrib subfolder of your work area.)

  3. Build and run the application in Visual Studio .NET.