Returns the height of an item in the System.Windows.Forms.ListBox.
The height, in pixels, of the specified item.
If the ListBox.DrawMode property is not set to DrawMode.OwnerDrawVariable, the value of the index parameter is ignored because all items in a standard System.Windows.Forms.ListBox are the same size. You can use this property when you are using an owner-drawn System.Windows.Forms.ListBox to determine the size of any item within the System.Windows.Forms.ListBox.