Comments by MehdiNaseri (Top 14 by date)

Reason for my vote of 5 \n Simple but effective method.
1) You can eliminate these two lines of code:
FirstArrowXPos = e.GetPosition((sender as Control).Parent as Control).X - FirstXPos - 20;
FirstArrowYPos = e.GetPosition((sender as Control).Parent as Control).Y - FirstYPos - 20;

2) Also use respective canvas margins instead of 20 , like this:

(sender as Control).SetValue(Canvas.LeftProperty,
e.GetPosition((sender as Control).Parent as Control).X - FirstXPos – ConvasName.Margin.Left);

(sender as Control).SetValue(Canvas.TopProperty,
e.GetPosition((sender as Control).Parent as Control).Y - FirstYPos - ConvasName.Margin.Left);