实现VB界面下的信号fft变换。界面提供两个波形的卷积，然后对其求FFT变换并显示-VB interface to achieve a signal fft transform. Interface convolution of two waveforms, and then seek its FFT transform and display

老外用vb实现的fft，快速傅里叶变换算法，有cls文件，而且有简单的demo，方便使用。-Foreigners with vb achieved fft, fast Fourier transform algorithm, there is cls files, but also a simple demo, easy to use.

采用vb语音编写时域抽取法的基2快速傅里叶变换，并以N=8为例验证了程序的正确性-Written in the time domain using vb speech extraction method of the base 2 Fast Fourier Transform, and N = 8 as an example to verify the correctness of the program