---
title: Render the alphanumeric filter bar
summary: Provide an A-Z-plus-numeric filter bar that the host page can use to filter its data.
status: draft
owner: SAIF Doc Gen
last_reviewed: 2026-08-17
library: SAIF.Presentation.Web.Controls.V2
reference_type: package
operation_id: OP-V2-015
trigger: "`CreateChildControls` for a `SAIFAlphaNumericLinkControl` instance; user click on a rendered link."
---

# Render the alphanumeric filter bar

Provide an A-Z-plus-numeric filter bar that the host page can use to filter its data. `CreateChildControls` for a `SAIFAlphaNumericLinkControl` instance; user click on a rendered link.

| Field | Value |
| --- | --- |
| **Operation ID** | OP-V2-015 |
| **Trigger** | `CreateChildControls` for a `SAIFAlphaNumericLinkControl` instance; user click on a rendered link. |
| **Inputs** | None (fixed A-Z + Number range). |
| **Outputs** | One `SAIFLinkButton` per letter plus a `Number` link; `LinkClicked` event carrying the clicked value. |
| **Primary components** | `SAIFAlphaNumericLinkControl` |
| **Entry point** | `SAIF.Presentation.Web.Controls.V2/SAIFAlphaNumericLinkControl.vb` |

## Steps

1. On `CreateChildControls`, create one `SAIFLinkButton` for each ASCII code 65-90 (`A`-`Z`), assigning the corresponding `AlphaNumericCharacter` value. ([BR-V2-089](../business-rules.md#br-v2-089-alphanumeric-bar-always-renders-the-full-a-z-range))
2. Append one additional link whose value is `AlphaNumericCharacter.Number`. ([BR-V2-090](../business-rules.md#br-v2-090-a-single-number-link-represents-all-numeric-values))
3. Raise `LinkClicked` with the clicked link's `AlphaNumericCharacter` value so the host page can filter its data. ([BR-V2-091](../business-rules.md#br-v2-091-clicked-character-delivered-via-linkclicked-event))

## Process flow

The following diagram visualizes this operation's control flow.

```mermaid
flowchart TD
	Start([CreateChildControls]) --> Loop[Create A-Z SAIFLinkButtons]
	Loop --> Num[Append Number link]
	Num --> Wait([Await user click])
	Wait --> Click[User clicks a link]
	Click --> Event[Raise LinkClicked with AlphaNumericCharacter]
```

## Failure and edge-case behavior

- No exceptional failure handling beyond the branches described in **Steps** was found in the analysis findings.*

## Related documentation
- [Operations and processes](../operations-processes.md)
- [Business rules](../business-rules.md)

## Sources
- `SAIF.Presentation.Web.Controls.V2/SAIFAlphaNumericLinkControl.vb`