num height

The height of this rectangle.

This is equivalent to the height function in jQuery and the calculated height CSS value, converted to a dimensionless num in pixels. Unlike getBoundingClientRect, height will return the same numerical width if the element is hidden or not.

Source 

num get height;
void height=(newHeight)

Set the height to newHeight.

newHeight can be either a num representing the height in pixels or a Dimension object. Values of newHeight that are less than zero are converted to effectively setting the height to 0. This is equivalent to the height function in jQuery and the calculated height CSS value, converted to a num in pixels.

Note that only the content height can actually be set via this method.

Source 

set height(newHeight) {
  throw new UnsupportedError("Can only set height for content rect.");
}