Fix FluentKeyCodeProvider error on using browser autocomplete with InputText

[najlot]

Pull Request

📖 Description

Hello everyone!
I've been trying to get FluentUI Blazor into an existing Blazor WebAssembly application.
After I've added FluentUI.Blazor like it is described in
https://v5.fluentui-blazor.net/installation
i've got an error as I tried to log in.

So there is a fix for that.

Stack trace I've got:

Message=
Source=
StackTrace:
at System.Text.Json.ThrowHelper.ThrowInvalidOperationException_ExpectedNumber(JsonTokenType tokenType)
at System.Text.Json.Utf8JsonReader.TryGetInt32(Int32& value)
at System.Text.Json.Utf8JsonReader.GetInt32()
at System.Text.Json.Serialization.Converters.Int32Converter.Read(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options)
at System.Text.Json.Serialization.JsonConverter1[[System.Int32, System.Private.CoreLib, Version=10.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].TryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, Int32& value, Boolean& isPopulatedValue) at System.Text.Json.Serialization.JsonConverter1[[System.Int32, System.Private.CoreLib, Version=10.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].ReadCore(Utf8JsonReader& reader, Int32& value, JsonSerializerOptions options, ReadStack& state)
Exception_EndOfInnerExceptionStack
at System.Text.Json.ThrowHelper.ReThrowWithPath(ReadStack& state, Utf8JsonReader& reader, Exception ex)
at System.Text.Json.Serialization.JsonConverter1[[System.Int32, System.Private.CoreLib, Version=10.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].ReadCore(Utf8JsonReader& reader, Int32& value, JsonSerializerOptions options, ReadStack& state) at System.Text.Json.Serialization.Metadata.JsonTypeInfo1[[System.Int32, System.Private.CoreLib, Version=10.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].Deserialize(Utf8JsonReader& reader, ReadStack& state)
at System.Text.Json.Serialization.Metadata.JsonTypeInfo`1[[System.Int32, System.Private.CoreLib, Version=10.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].DeserializeAsObject(Utf8JsonReader& reader, ReadStack& state)
at System.Text.Json.JsonSerializer.ReadAsObject(Utf8JsonReader& reader, JsonTypeInfo jsonTypeInfo)
at System.Text.Json.JsonSerializer.Deserialize(Utf8JsonReader& reader, Type returnType, JsonSerializerOptions options)
at Microsoft.JSInterop.Infrastructure.DotNetDispatcher.ParseArguments(JSRuntime jsRuntime, String methodIdentifier, String arguments, Type[] parameterTypes)
at Microsoft.JSInterop.Infrastructure.DotNetDispatcher.InvokeSynchronously(JSRuntime jsRuntime, DotNetInvocationInfo& callInfo, IDotNetObjectReference objectReference, String argsJson)
at Microsoft.JSInterop.Infrastructure.DotNetDispatcher.BeginInvokeDotNet(JSRuntime jsRuntime, DotNetInvocationInfo invocationInfo, String argsJson)
at w.endInvokeDotNetFromJS (http://localhost:5270/_framework/blazor.webassembly.w3qd1tpl0e.js:1:4504)
at Object.tn [as endInvokeDotNetFromJS] (http://localhost:5270/_framework/blazor.webassembly.w3qd1tpl0e.js:1:59313)
at http://localhost:5270/_framework/dotnet.runtime.web2r9gqbh.js:3:34587
at Mc (http://localhost:5270/_framework/dotnet.runtime.web2r9gqbh.js:3:175837)
at http://localhost:5270/_framework/dotnet.native.u31nt9bth6.wasm:wasm-function[298]:0x1f797
at http://localhost:5270/_framework/dotnet.native.u31nt9bth6.wasm:wasm-function[222]:0x1ca98
at http://localhost:5270/_framework/dotnet.native.u31nt9bth6.wasm:wasm-function[213]:0xebe7
at http://localhost:5270/_framework/dotnet.native.u31nt9bth6.wasm:wasm-function[256]:0x1d974
at http://localhost:5270/_framework/dotnet.native.u31nt9bth6.wasm:wasm-function[3231]:0xf1888
at http://localhost:5270/_framework/dotnet.native.u31nt9bth6.wasm:wasm-function[2553]:0xc7139

🎫 Issues

No issue created as there is the fix.

👩‍💻 Reviewer Notes

There is what I've done:

📑 Test Plan

I've got an simple example app where the issue can be reproduced:
example_app.zip

✅ Checklist

General

• I have added tests for my changes.
• I have tested my changes. -> I've had some issues to get the project running in my project
• I have updated the project documentation to reflect my changes. -> I could not find documentation that need changes.
• I have read the CONTRIBUTING documentation and followed the standards for this project.

Component-specific

• I have modified an existing component
• I have validated the Unit Tests for an existing component

⏭ Next Steps

[najlot]

@microsoft-github-policy-service agree

[Copilot]

Pull request overview

This PR hardens the FluentKeyCode JavaScript interop against malformed/partial keyboard events (e.g., events missing numeric/boolean properties), preventing System.Text.Json deserialization failures when Blazor receives the event payload.

Changes:

• Normalize keyboard event fields (keyCode, modifier flags, location, repeat, key) before invoking .NET (invokeMethodAsync) to ensure stable argument types.
• Add a Playwright integration test + minimal Razor page that reproduces a “keydown event missing properties” scenario and asserts the component reports default values instead of throwing.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
tests/Integration/Components/KeyCode/FluentKeyCodeTests.cs	Adds an integration test that dispatches a malformed keydown event and verifies default output values.
tests/Integration/Components/KeyCode/Examples/MalformedKeyboardEventPage.razor	Adds a dedicated test page wiring FluentKeyCode to an input and rendering observed event values for assertions.
src/Core/Components/KeyCode/FluentKeyCode.razor.ts	Normalizes event argument types before JS→.NET invocation to avoid JSON token type errors.

[dvoituron]

Need more time to validate 😊