Number of node items. Some nodes are in array format. Lists are the most common example.
In the example below, since the list has 3 sub-nodes, the NodeCount is 3. If you do not know the number of list elements beforehand, etc. it is good to first read out NodeCount and loop it for the number of repetitions.
In the example below, there is one u2 item, 2 u4 items, and three f8 items in the NodeCount.
<u4 1024 4096>
<f8 1.05 2.26 3.14>
The NodeCount of the following list is 0.