---
title: SAIFComboBox
summary: API reference for SAIFComboBox.
status: draft
owner: SAIF Documentation Team
last_reviewed: 2026-08-17
library: SAIF.Presentation.Web.Controls.V2
reference_type: package
---

# SAIFComboBox

`SAIFComboBox` is a `DropDownList` subclass adding the same AJAX "busy indicator" client-side convention as `SAIFButton`/`SAIFListBox`, applied to dropdown selection changes rather than button clicks.

## Purpose
- Give dropdown selection changes a consistent "in-progress" visual indicator during AJAX partial postbacks.
- Optionally disable other form controls while the selection-change postback is in flight.

## Context
- Namespace: `SAIF.Presentation.Web.Controls.V2`
- Assembly/package: Compiled into `SAIF.BOF.Presentation.Web.Infragistics103`*

## Public members
| Member | Signature | Purpose |
| --- | --- | --- |
| `DisableFormControlsOnChange` | `Public Property DisableFormControlsOnChange As Boolean` | Determines whether other form controls are disabled client-side while this dropdown's change postback is processed; defaults to `True`. |
| `EnableIndicator` | `Public Property EnableIndicator As Boolean` | Turns on the AJAX busy-indicator CSS class and registers the supporting client script; defaults to `True`. |

## Inherited public members

`SAIFComboBox` inherits from `DropDownList` (`System.Web.UI.WebControls`), a framework base class rather than a documented SAIF dependency library.

| Member | Signature | Purpose |
| --- | --- | --- |
| `AppendDataBoundItems` | `Public Property AppendDataBoundItems As Boolean` | Determines whether data binding appends to existing items instead of replacing them. |
| `AutoPostBack` | `Public Property AutoPostBack As Boolean` | Determines whether changing the selection immediately posts the page back to the server. |
| `DataTextField` | `Public Property DataTextField As String` | Name of the data-source field used for item display text during binding. |
| `DataValueField` | `Public Property DataValueField As String` | Name of the data-source field used for the posted item value during binding. |
| `Items` | `Public ReadOnly Property Items As ListItemCollection` | Collection of selectable dropdown items managed by the control. |
| `SelectedIndex` | `Public Property SelectedIndex As Integer` | Zero-based index of the currently selected item. |
| `SelectedItem` | `Public ReadOnly Property SelectedItem As ListItem` | Currently selected dropdown item. |
| `SelectedValue` | `Public Property SelectedValue As String` | Posted value of the currently selected item. |
| `Text` | `Public Property Text As String` | Display text associated with the selected item. |
| `SelectedIndexChanged` | `Public Event SelectedIndexChanged As EventHandler` | Standard selection-change event raised after postback. |

Standard `DropDownList`/`Control` members (`ID`, `ClientID`, `Controls`, `Visible`, `DataBind`, `FindControl`, etc.) are not re-documented here as they are unmodified framework behavior**.

## Behavioral notes
- `SAIFComboBox_Init` sets `CssClass` to `"SAIFComboBox"`, or `"SAIFComboBoxIndicator"` plus a `DisableFormControls` attribute when `EnableIndicator` is true, and registers `ComboBox.js` in that case.
- The `ComboBox.js` script referenced is not present in this project folder; its exact client-side indicator behavior could not be verified from this library's source**.

## Constraints and usage notes
- Requires `ComboBox.js` to be deployed at `/Resources/Scripts/Controls/ComboBox.js` in the hosting application for the indicator behavior to function.
- Distinct from `SAIFDropDownList`, which instead provides `[ReadOnly]` rendering and enum data binding rather than an AJAX indicator.

> **Note:** Statements marked with * were inferred from code structure, naming conventions, or
> contextual evidence where direct confirmation was not available in source artifacts. Statements
> marked with ** could not be confirmed; treat as unknown until verified.

## Sources
- SAIF.Presentation.Web.Controls.V2\SAIFComboBox.vb