Canvas.Width和Canvas.height返回-1＃.IND

Question

当我尝试获取画布的宽度和高度时，都返回-1＃.IND

Dim ControlWidth as double = MyCanvas.Width 
Dim ControlHeight as double = MyCanvas.Height 

Answer 1

-1#.IND为Double.NaN，表示宽度和高度设置为auto。要获得以像素为单位的维度（/ units？），您应该使用ActualWidth和ActualHeight。

Dim ControlWidth As Double = MyCanvas.ActualWidth 
Dim ControlHeight As Double = MyCanvas.ActualHeight