WPF-SurfacePlot3D is a tiny C# library containing easy-to-use 3D surface plotting components for WPF (.NET) applications.
You can get started in as few as four lines:
var myPlot = new SurfacePlotViewModel();
myPlotView.DataContext = myPlot;
function = (x, y) => x * y;
viewModel.PlotFunction(function, -1, 1);
Check out the documentation for more information!