101 Rx Examples


Answer :

I actually had similar thoughts a couple days ago. We started our own "101 Rx Samples" as a post in the Rx MSDN forum, but we have since moved it to a Wiki format. Please feel free to come over and add your own samples!

101 Rx Samples on the Rx wiki


To start with - Here is a simple drawing application, so that when the user drags, we draw a red line from the initial mouse down position to the current location, and also a blue spot at the current location. This is the result of my last week's hack on Rx

A WPF Drawing Demo

And here is the source code.

//A draw on drag method to perform the draw void DrawOnDrag(Canvas e)         {              //Get the initial position and dragged points using LINQ to Events             var mouseDragPoints = from md in e.GetMouseDown()                                   let startpos=md.EventArgs.GetPosition(e)                                   from mm in e.GetMouseMove().Until(e.GetMouseUp())                                   select new                                   {                                       StartPos = startpos,                                       CurrentPos = mm.EventArgs.GetPosition(e),                                   };               //Subscribe and draw a line from start position to current position             mouseDragPoints.Subscribe                 (item =>                 {                     e.Children.Add(new Line()                     {                         Stroke = Brushes.Red,                         X1 = item.StartPos.X,                         X2 = item.CurrentPos.X,                         Y1 = item.StartPos.Y,                         Y2 = item.CurrentPos.Y                     });                      var ellipse = new Ellipse()                     {                         Stroke = Brushes.Blue,                         StrokeThickness = 10,                         Fill = Brushes.Blue                     };                     Canvas.SetLeft(ellipse, item.CurrentPos.X);                     Canvas.SetTop(ellipse, item.CurrentPos.Y);                     e.Children.Add(ellipse);                 }                 );         }

Read my post with further explanation here and Download the source code here

Hope this helps


Another useful resource may be the Reactive Extensions (Rx) Koans: 55 progressive examples to help you learn Rx


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