Bounding Extent Box method was introduced in V5
This XYZ bounding box extents measurement can be over any collection of objects ( including a *single cylinder) outputting relative to global XYZ or to a local origin if additionally selected
Triple click a cylindrical face or box select it, key E for measure and a Bounding Box XYZ extents are output.
* The easiest way for just a cylinder, is select it's 2 edges or bounding planes for an auto distance output as has been mentioned earlier.
Cylinder length measurement
Object collection - quite useful.