`). Remove `runat="server"` — use `@ref` if the element needs programmatic access.
### String Format in Binding
```xml
<%#: string.Format("{0:C}", Item.Price) %>
@Item.Price.ToString("C")
```
### Visibility Pattern
```xml
...
...
@if (showPanel)
{
...
}
```
### Nested Master Pages
Web Forms supports nested Master Pages. In Blazor, use nested layouts:
```razor
@* ChildLayout.razor *@
@inherits LayoutComponentBase
@layout MainLayout
@Body
```
---
## Attributes Removed During Migration
These Web Forms attributes have no Blazor equivalent and should be silently removed:
- `runat="server"` — always remove
- `AutoEventWireup="true"` — no equivalent
- `CodeBehind="X.aspx.cs"` — no equivalent (use `.razor.cs` convention)
- `CodeFile="X.aspx.cs"` — same as CodeBehind
- `Inherits="Namespace.Class"` — use `@inherits` only if needed
- `EnableViewState="false"` — no ViewState in Blazor
- `ViewStateMode="Disabled"` — no ViewState in Blazor
- `ValidateRequest="false"` — no request validation in Blazor
- `MaintainScrollPositionOnPostBack="true"` — no postback in Blazor
- `ClientIDMode="Static"` — no client ID munging in Blazor
- `EnableTheming="false"` — not applicable
- `SkinID="X"` — use BWFC theming system if needed
---
## BWFC Component Coverage
**52 components** across 7 categories:
| Category | Components |
|----------|-----------|
| **Editor Controls** | AdRotator, BulletedList, Button, Calendar, CheckBox, CheckBoxList, DropDownList, FileUpload, HiddenField, HyperLink, Image, ImageButton, Label, LinkButton, ListBox, Literal, Localize, MultiView, Panel, PlaceHolder, RadioButton, RadioButtonList, Table, TextBox, View |
| **Data Controls** | DataGrid, DataList, DataPager, DetailsView, FormView, GridView, ListView, Repeater |
| **Validation Controls** | CompareValidator, CustomValidator, ModelErrorMessage, RangeValidator, RegularExpressionValidator, RequiredFieldValidator, ValidationSummary |
| **Navigation Controls** | Menu, SiteMapPath, TreeView |
| **Login Controls** | ChangePassword, CreateUserWizard, Login, LoginName, LoginStatus, LoginView, PasswordRecovery |
| **AJAX Controls** | ScriptManager, ScriptManagerProxy, Timer, UpdatePanel, UpdateProgress |
---
## WingtipToys-Specific Patterns
The WingtipToys canonical demo (2013) uses these specific patterns that BWFC fully supports:
| WingtipToys Pattern | BWFC Migration |
|---------------------|---------------|
| `ItemType="WingtipToys.Models.Product"` | `TItem="Product"` |
| `SelectMethod="GetProducts"` | `Items="products"` (load in `OnInitializedAsync`) |
| `
` with `LayoutTemplate`/`GroupTemplate` | `` — templates preserved |
| `` with `RenderOuterTable="false"` | `` ✅ |
| `` with `BoundField` + `TemplateField` | Same column types in BWFC |
| ASP.NET Identity login/register | Migrate to Blazor Identity (separate from BWFC) |
| Shopping cart with `Session` state | Replace with scoped service + `ProtectedSessionStorage` |
| `~/` route prefix | Replace with `/` |
| `` | `` ✅ |
---
## Files to Create During Migration
For a typical Web Forms → Blazor migration, create these files:
1. **`Program.cs`** — Service registration, middleware pipeline
2. **`Properties/launchSettings.json`** — Environment config for `dotnet run`
3. **`App.razor`** — Root component with Router
4. **`_Imports.razor`** — Global usings including BWFC namespaces
5. **`Components/Layout/MainLayout.razor`** — From Master Page
6. **`Components/Pages/*.razor`** — One per .aspx page
7. **`Services/*.cs`** — Replace DataSource controls and code-behind data methods
8. **`Models/*.cs`** — Copy/migrate from Web Forms project (often .NET Standard already)
---
## Identity & Authentication Migration
ASP.NET Web Forms Identity uses `SignInManager` and forms authentication cookies, which require an active HTTP response. In Blazor Server (SignalR), there is no HTTP response after the initial page load. This requires a different pattern.
### Authentication Endpoints
Authentication operations (login, logout, register) must be HTTP endpoints, NOT Blazor component handlers:
```csharp
// Program.cs — HTTP endpoints for auth operations
// Login: SignInManager needs HTTP context to set auth cookies
app.MapGet("/Account/PerformLogin", async (
string email, string password,
SignInManager signInManager) =>
{
var result = await signInManager.PasswordSignInAsync(email, password,
isPersistent: false, lockoutOnFailure: false);
if (result.Succeeded)
return Results.Redirect("/");
return Results.Redirect("/Account/Login?error=" +
Uri.EscapeDataString("Invalid login attempt."));
});
// Logout: must be POST for CSRF protection
app.MapPost("/Account/PerformLogout", async (
SignInManager signInManager) =>
{
await signInManager.SignOutAsync();
return Results.Redirect("/");
});
```
### Login Page Pattern
The Login page is an InteractiveServer component that collects credentials, then navigates to the HTTP endpoint with `forceLoad: true`:
```csharp
private void HandleLogin(MouseEventArgs args)
{
var loginUrl = $"/Account/PerformLogin?email={Uri.EscapeDataString(email)}" +
$"&password={Uri.EscapeDataString(password)}";
NavigationManager.NavigateTo(loginUrl, forceLoad: true);
}
```
### Logout Form Pattern
The logout button must be a plain HTML form (not a Blazor form) that posts to the HTTP endpoint. Use `data-enhance="false"` to prevent Blazor enhanced navigation from intercepting:
```razor
```
> **⚠️ CRITICAL:** Without `data-enhance="false"`, Blazor intercepts the form POST and tries to handle it as a Blazor form submission, which fails because there's no matching `@formname` handler.
### AuthorizeView in Layout
Replace Web Forms `` with ``:
```razor
Hello, @context.User.Identity?.Name!
Register
Log in
```