DropDownTree Load on Demand

Updated on Aug 24, 2026

This article explains how to load flat and hierarchical data on demand in the DropDownTree for Blazor. Before continuing, make sure you are familiar with the DropDownTree data binding basics.

You can bind the DropDownTree to just one or two levels on initial display for efficiency. To show an expand icon for parent items and enable loading of children on demand, set the HasChildren property of the parent item to true. Then, use the OnExpand event to load the child items of the expanded node. Loading data on demand can improve the performance of your application by requesting less data at any given time.

Flat Data

Load DropDownTree items on demand with flat data

Example

View Source

Loading ...

Hierarchical Data

Load DropDownTree items on demand with hierarchical data

Example

View Source

Loading ...

See Also

• DropDownTree Data Binding Basics
• DropDownTree Binding to Flat Data
• DropDownTree Binding to Hierarchical Data
• Live Demo: DropDownTree Demos