[Expand]General Information
[Expand]WinForms Controls
[Collapse]ASP.NET Controls and MVC Extensions
 [Expand]What's Installed
 [Expand]Common Concepts
 [Collapse]ASP.NET WebForms Controls
   Getting Started
  [Expand]Grid View
  [Expand]Tree List
  [Expand]Card View
  [Expand]Chart Control
  [Expand]Pivot Grid
  [Expand]Rich Text Editor
  [Expand]Site Navigation and Layout
  [Expand]HTML Editor
  [Expand]Vertical Grid
  [Collapse]Data Editors
   [Expand]Product Information
   [Expand]Common Concepts
   [Collapse]Editor Types
      ASPxComboBox Overview
       Incremental Filtering of ASPxComboBox
       Custom Filtering
      [Collapse]Item Loading Modes
        Default Item Loading Mode
        On-Demand Item Loading (Callback Mode)
        Dynamic List Population (Filtering Large Data Sources)
  [Expand]Docking and Popups
  [Expand]File Management
  [Expand]Data and Image Navigation
  [Expand]Multi-Use Site Controls
  [Expand]Spell Checker
  [Expand]Query Builder
 [Expand]ASP.NET MVC Extensions
 [Expand]Redistribution and Deployment
  Get More Help
 [Expand]API Reference
[Expand]ASP.NET Bootstrap Controls
[Expand]ASP.NET Core Bootstrap Controls
[Expand]WPF Controls
[Expand]Xamarin Controls
[Expand]Windows 10 App Controls
[Expand]Office File API
[Expand]Report and Dashboard Server
[Expand]eXpressApp Framework
[Expand]CodeRush Classic
[Expand]Cross-Platform Core Libraries
[Expand]Tools and Utilities
 End-User Documentation

Default Item Loading Mode

By default, the ASPxComboBox editor obtains its items in the following manner:

  1. The editor retrieves all data items from the bound data source (defined via the ASPxAutoCompleteBoxBase.DataSourceID or ASPxAutoCompleteBoxBase.DataSource property) and loads them in the application server's memory;
  2. The editor sends all list items to the client side, to be presented within the editor's dropdown list.

In this mode, since all list items are represented on the client, all data operations (such as scrolling, filtering) are performed on the client, without generating a round trip to the server.

This default mode is well suited to the task if the ASPxComboBox editor works with a small data sample - that is, the Multi-Column Mode is not used (or there is a rather small number of columns) and the number of data source items is not great (numbered in tens or hundreds rather than thousands). For larger amounts of data, it might be sensible to use the On-Demand Item Loading or Dynamic List Population mode.

Is this topic helpful?​​​​​​​