---
title: Page-wide auto-bind and validate
summary: Walks the page control tree, assigns the model to every auto-binding control, and aggregates validity.
status: draft
owner: SAIF documentation generator
last_reviewed: 2026-08-17
library: SAIF.Presentation.Web.Controls.AJAX.Infragistics103
reference_type: package
operation_id: OP-AJAX-001
trigger: Hosting ASPX page invokes BindingManager.DataBind() once its model object is available
---

# Page-wide auto-bind and validate

`BindingManager` is the page-level orchestrator for every auto-binding control on an ASPX page. The hosting page invokes `BindingManager.DataBind()` (typically in `Page_Load`/`Page_PreRender`) once the page's model is available; the method recursively walks `Page.Controls`, assigns the resolved model (`RootObject`) to each discovered `iAutoBindingControl`, and later exposes aggregated `IsValid`/`ErrorMessages` across the whole page.

| Field | Value |
| --- | --- |
| **Operation ID** | OP-AJAX-001 |
| **Trigger** | Hosting page calls `BindingManager.DataBind()`, typically from `Page_Load`/`Page_PreRender` |
| **Inputs** | `Page.Controls` tree; a `RootObject` resolved from the page's `"Model"` property |
| **Outputs** | Every discovered auto-binding control is data-bound to the model; `IsValid`/`ErrorMessages` reflect the aggregate binding state |
| **Primary components** | `BindingManager.DataBind`, `BindingManager.GetRootObject`, `BindingManager.IsValid`, `BindingManager.ErrorMessages` |
| **Entry point** | `SAIF.Presentation.Web.Controls.AJAX.Infragistics103\BindingManager.vb` |

## Steps

1. `RootObject` getter resolves the bound model via `BindingUtility.GetObjectValue(Page, "Model")` if not already cached.
2. `DataBind()` recursively walks `Page.Controls` (private `DataBind(inControls)` overload).
3. For each leaf control, `BindControl` checks whether the control (or its `BindingContainer`) implements `iAutoBindingControl`; if so, its `RootBindingObject` is set to `RootObject`. No SQL/table access occurs at this step.
4. Each bound `iAutoBindingControl`'s own `DataBind()` then executes as part of the standard ASP.NET control lifecycle when the framework calls `DataBind()` on the control tree.
   - See [Auto-bind an individual control to its bound object](auto-bind-an-individual-control-to-its-bound-object.md) for the per-control logic.
5. `IsValid` (read-only) recursively calls `CheckValidControls` over `Page.Controls`, returning `False` on the first control whose `iAutoBindingControl.IsValid` is `False`.
6. `ErrorMessages` recursively collects and de-duplicates error strings from every `iAutoBindingControl.ErrorMessages` into an HTML `<br>`-joined string (`GetErrorMessages`, `AppendUniqueMessages`).

## Process flow

The following diagram visualizes this operation's control flow.

```mermaid
flowchart TD
	Start([Page invokes BindingManager.DataBind]) --> Walk[Recursively walk Page.Controls]
	Walk --> Check{Control implements iAutoBindingControl?}
	Check -->|Yes| Assign[Set RootBindingObject on control]
	Check -->|No| Next[Continue to next control]
	Assign --> CtrlDataBind[ASP.NET lifecycle invokes control's own DataBind]
	CtrlDataBind --> Aggregate[IsValid/ErrorMessages aggregate across all controls]
```

## Failure and edge-case behavior
- No page model (`"Model"` property returns `Nothing`): `RootObject` resolves to `Nothing`; downstream controls receive a `Nothing` `RootBindingObject` and their own `DataBind()` will no-op (see the per-control operation).

## Related documentation
- [Operations and processes](../operations-processes.md)
- [Business rules](../business-rules.md)
- [SQL catalog](../sql/index.md)
- [Database tables](../database-tables.md)

## Sources
- `SAIF.Presentation.Web.Controls.AJAX.Infragistics103\BindingManager.vb`
- `SAIF.Presentation.Web.Controls.AJAX.Infragistics103\BindingUtility.vb`
- `SAIF.Presentation.Web.Controls.AJAX.Infragistics103\iAutoBindingControl.vb`