Adds support for Razor templates and RenderFragment<T>.
Razor templates are a little-known Razor feature that looks like:
```
@<tag>....<tag>
```
It's so little known that it's not even covered in our docs, but it's
been around for many many years. This features hasn't been implemented
until now for Blazor, and this feature brings it back as a build
building block for templated components (more to come).
In Blazor land a template like:
```
@{ RenderFragment<Person> template = @<div>@item.Name</div>; }
```
complies to code like:
```
RenderFragment<Person> template = (__builder, item) =>
{
__builder.OpenElement(...);
...
__builder.CloseElement(...);
}
```
Since the declaration always has a generic type parameter inside, it
needs to be in a context where the type is known.. ie: not with `var`.
See tests for ways to consume templates.
NOTE: There are the following caveats for templates
- Templates require a single root element.
- Templates don't work in the `@functions { }` block
These limitations are baked into the core of Razor and will take a while
for us to address (v3.0).
* Reenable HtmlBlock unit tests
* Add E2E tests for HTML Block cases
* Remove harded GenerateBaselines=true
* Fix#1193
This commit addresses the root cause of #1193. When we merge HTML
text nodes into HTML blocks we need to re-encode any HTML entities that
were encoded eariler.
I did a bit of a deep dive on how HTML encoding is handled in Blazor and
I think this is the best strategy. I think it's valuable that the
BrowserRenderer uses document.createTextNode, which will always encode
the text - this handles dynamic content. We want to keep this in place
to avoid HTML injection attacks.
* Fix#1265 Reenable MarkupBlock
* test cleanup
* Add HTML Block rewriter
* Baseline updates
* test gaps
* Update some unit tests to represent same behavior as before
* Define Markup frame type. Tests for rendering markup frames into render tree.
* Support markup frames during diffing (retain, insert, update, delete)
* Support markup blocks on WebAssembly
* Support rendering markup frames with server-side execution too
* Support markup blocks with multiple top-level nodes. Support updating markup dynamically.
* Define MarkupString type as a way to insert dynamic markup without needing custom RenderFragment code
* Remove comment
* CR: Better null value handling
The root cause here was that we weren't setting the language version in
MSBuild, which is only for the command line version.
(cherry picked from commit 319e31f71a150e9b0d91e724f0e358390caec4c2)
* Implement OnAfterRender and OnAfterRenderAsync
* Add E2E test combining OnAfterRender with "ref" and JS interop
... because this combination is the key to integration with 3rd-party JS
libs
* Factor out all DOM-structure modifying code into an abstraction. Currently, implementation is still backed by the same underlying DOM APIs
* Implement LogicalElement properly (store hierarchy in own property; use comment nodes as containers)
* In LogicalElement, be explicit about unsupported scenarios
* Update E2E tests to stop assuming existence of wrapper elements
* Where supported, store private properties using opaque symbols as keys
* Improve support for more types of event handlers
Improves support for for other types of event handlers with eventargs
types derived from UIEventArgs. Additionally fleshes out the set of
event handler types.
This change improves support for using more specific event handler types
like:
```
<button onclick="@Clicked" />
@functions {
public void Clicked(UIMouseEventArgs e) { ... }
}
```
And:
```
builder.AddAttribute(12, "onkeypressed", KeyPressed);
...
void KeyPressed(UIKeyboardEventArgs e) { ... }
```
In particular what got better is:
- overload resolution for the AddAttribute method
- performance of different cases for AddAttribute
-----
The runtime now treats delegates as one of three types:
- arbitrary delegate: not attached to DOM events, not tracked by
renderer
- UIEventHandler: can attach to DOM events, tracked by renderer, first
class in IHandleEvents
- UIEventHandler-like: can attach to DOM events, tracked by renderer,
requires some special runtime support.
The set of overloads on AddAttribute has been tuned with a few specific
cases in mind.
Lambda expressions in an attribute will be inferred as UIEventHandler
unless the compiler does something more specific. So for instance,
passing a lambda as an attribute value for a component, where the
component doesn't define a matching attribute, will always be inferred
as UIEventHandler.
We now support method-group to delegate conversion for methods that
accept a derived UIEventArgs type. This means you can use a signature
like `void KeyPressed(UIKeyboardEventArgs e)` without any compiler
magic, and this will work in the runtime as long as the event type
produced by the runtime matches.
We also allow user-defined UIEventArgs-derived types. There's a pattern
for this and it requires defining an extension method and delegate type.
The method-group to delegate conversion part required some doing. It
doesn't play well with generics (Action<T> where T : UIEventArgs)
doesn't work at all. Adding more actual overloads (as opposed to
extensions) would cause lambda cases we want to work to be ambiguous.
----
The performance win here is to remove the need for a 'wrapper' delegate
created by the event handler tag helper code. This wrapper is now
created by the runtime, but only *after* we have checked the frame for
changes. This requires more heavy lifting in the runtime, but has the
advantage of producing no-op diffs as often as possible.
You will still get some inefficient behavior if your component uses a
capturing lambda in an event handler, so don't do that.
* Add selenium logs to test output
* Minor feedback
* WIP
* On build, drop <BlazorPackageContentFiles> items into dist\_content\(PackageName)\
* Add <script> and <link> tags to generated index.html
* Add testapp coverage of external content package. Still need to add E2E tests that uses it.
* Add missing unit test update
* Add example of packaging an entire Blazor component including CSS and images
* Add E2E test for component from NuGet package
Ryan Nowak
Steve Sanderson
Ryan Nowak
Stephen Roe