---
title: mdlTextConversion
summary: API reference for mdlTextConversion.
status: draft
owner: <owner>
last_reviewed: 2026-07-24
library: SAIF.Business.Utilities
reference_type: package
---

# mdlTextConversion

`mdlTextConversion` is a public module providing numeric-to-English-words conversion (typically for printed check/dollar amounts) and a sentence-case string extension.

## Purpose
- Convert a `Long` numeric value into its spelled-out English-words representation.
- Provide a `ToSentenceCase` extension method for sentence-style string capitalization.

## Context
- Namespace: `SAIF.Business.Utilities`
- Assembly/package: `SAIF.Business.Utilities` (NuGet package `SAIF.BOF.Business.Utilities`)

## Public members
| Member | Signature | Purpose |
| --- | --- | --- |
| NumberToText | `Public Function NumberToText(n As Long) As String` | Recursively converts a `Long` numeric value into its English words representation (e.g., spelled-out check/dollar amounts). Supports values up to 999,999,999,999,999; throws `ApplicationException` above that limit. See [BR-002](../../business-rules.md#br-002-numeric-conversion-upper-bound). |
| ToSentenceCase | `<Extension()> Public Function ToSentenceCase(Target As String) As String` | Upper-cases the first character of a string and lower-cases the remainder. |

<!-- RoundDown is a private helper (Private Function RoundDown(inValue As Long, inDivisor As Long) As Integer) and is not part of the public surface. -->

## Behavioral notes
- `NumberToText` enforces an explicit upper bound of 999,999,999,999,999; calling it with a larger value throws `ApplicationException("Number too large to convert to text. Limit is 999,999,999,999,999.")`. See [BR-002](../../business-rules.md#br-002-numeric-conversion-upper-bound).
- `NumberToText` decomposes the input recursively by magnitude group (ones/teens, tens, hundreds, thousands, millions, billions, trillions), using the private `RoundDown` helper internally.
- `ToSentenceCase` only affects the first character's case; it does not perform per-word title-casing like `TitleCase.ToTitleCase`.

## Constraints and usage notes
- `NumberToText` is intended for positive integer amounts (e.g., dollar amounts on printed checks); behavior for negative values could not be confirmed from the scanned source.**

> **Note:** Statements marked with `**` could not be confirmed; treat as unknown until verified.

## Sources
- `Business\SAIF.Business.Utilities\mdlTextConversion.vb`