The key object for manipulating material properties, field sources and boundary conditions is a DataDoc object. It represents the Data (Property) document. Each DataDoc object is a member of one of the Documents collections that is accessible by the DataDocs property of the QuickField Application. You can also get a DataDoc object from the Problem. The Problem might have up to two associated DataDoc objects: the primary one is accessible by the DataDoc property and the secondary (if any) can be obtained by the Library property.
Each DataDoc inherits all the properties and methods from its parent IDocument interface, so you can create a new DataDoc, open an existing one, save it to disk and so on. A DataDoc object contains three collection of Label, one per each type of geometric entity: Vertices, Edges and Blocks. The Labels collection manages creating, copying, removing a renaming of the Label objects. The Label object provides the Edit method for editing the label content by the dialog box, and the Content property that allows obtaining and setting the physical data programmatically.
In general the sequence of actions when working with data proceeds as follows:
See the DataDoc topic for the chart and more detailed explanation.