---
title: ModelStateWrapper
summary: API reference for ModelStateWrapper.
status: draft
owner: SAIF Documentation
last_reviewed: 2026-09-17
library: SAIF.Framework.Web.Mvc
reference_type: package
---

# ModelStateWrapper

Implements `IMessageContainer` over `ModelStateDictionary`, giving domain/service code a validation-agnostic way to report errors, warnings, and informational messages while de-duplicating repeated text so users do not see the same message multiple times.

## Purpose
- Implements `IMessageContainer` over `ModelStateDictionary`, giving domain/service code a validation-agnostic way to report errors, warnings, and informational messages while de-duplicating repeated text so users do not see the same message multiple times.

## Context
- Namespace: `SAIF.Web.Mvc`
- Assembly/package: `SAIF.Framework.Web.Mvc (source-shipping NuGet package)`
- Kind: class (service)

## Public members
| Member | Signature | Purpose |
| --- | --- | --- |
| Warnings | `public IList<string> Warnings { get; }` | Accumulated warning messages, each appended at most once regardless of how many callers report the same text. |
| Informationals | `public IList<string> Informationals { get; }` | Accumulated informational messages, de-duplicated the same way as `Warnings`. |
| AddError(string propertyName, string message) | `public void AddError(string propertyName, string message)` | Adds a model-state error for the property, blanking the message text on repeat occurrences so it displays only once; see the "Collect user messages through ModelStateWrapper" operation. |
| AddWarning(string message) | `public void AddWarning(string message)` | Appends a warning only if no case-insensitive duplicate already exists. |
| AddInformation(string message) | `public void AddInformation(string message)` | Appends an informational message only if no case-insensitive duplicate already exists. |

## Behavioral notes
- `AddError` still creates a model-state entry for the property even when the message text is blanked out, so field-level error highlighting is preserved (see [BR-37](../../business-rules.md#br-37-duplicate-error-message-displayed-once-but-still-flags-the-field)).

## Sources
- `src/Web.Mvc/Classes/ModelStateWrapper.cs`