From Xojo Documentation

Read-Only Property (As Integer )
IntegerValue = aWebGraphics.Height

Supported for all project types and targets.

The height in pixels of the drawing areas of the parent WebCanvas.


This example gets the height of the parent WebCanvas and draws a line down the left edge:

Var h As Integer
h = g.Height
g.PenWidth = 5
g.DrawLine(0, 0, 0, h)