Parameter binding does not work in blazor #30178
Description
Describe the bug
Unable to bind parameters to component because every time I try - exceptions are thrown or compilation error is shown.
To Reproduce
Just checkout my public repo: https://github.com/pavlexander/BlazorBugTesting001/tree/master
It's a fresh latest WASM project, with added component as described in documentation.
Two scenarios failed for me:
Scenario 1
When using trying to bind the parameter like so:
<Child @bind-Year="year" />You will get an IntelliSense/compilation error like this one:
Severity Code Description Project File Line Suppression State
Error The attribute names could not be inferred from bind attribute 'bind-Year'. Bind attributes should be of the form 'bind' or 'bind-value' along with their corresponding optional parameters like 'bind-value:event', 'bind:format' etc. BlazorBugTesting001.Client C:\Users\pavne\source\repos\BlazorBugTesting001\BlazorBugTesting001\Client\Pages\Test2.razor
check file Test1.razor or Test2.razor for example.
Scenario 2
When using trying to bind the parameter like so:
<Child @bind-Year="year" @bind-Year:event="YearChanged" />The compilation error will be gone but you will get a runtime exception when visiting the page:
crit: Microsoft.AspNetCore.Components.WebAssembly.Rendering.WebAssemblyRenderer[100]
Unhandled exception rendering component: no idea on how to unbox value types
Error: no idea on how to unbox value types
check file Test4.razor for example.
I tried the code to work with the default configuration (as described in documentation) and trying to bind the property that is in a shared service (DI singleton). Both failed.
Final remarks
Also take into the consideration that I am following the official documentation here.. If something has changed in how Blazor works - please update it and let me know why each of the 2 scenarios fail.
Further technical details
lots of text ahead
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5.0.102 [C:\Program Files\dotnet\sdk]
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Microsoft.AspNetCore.All 2.1.25 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
Microsoft.AspNetCore.App 2.1.24 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
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Microsoft.AspNetCore.App 3.1.12 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 5.0.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 5.0.3 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
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Microsoft.NETCore.App 3.1.12 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 5.0.2 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
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Microsoft.WindowsDesktop.App 5.0.3 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]