EditorTemplateView option does not accept PartialAsync() method

[kendo-bot]

Bug report

When loading an editor through a partial View using EditorTemplateView(await Html.PartialAsync("PartialViewName")), the following error occurs:

The 'await' operator can only be used within an async lambda expression. Consider marking this lambda expression with the 'async' modifier.

Reproduction of the problem

@(Html.Kendo().Form<UserViewModel>()
     .Name("myForm")
     .Items(items =>
     {
         items.Add().Field(f => f.Username).EditorTemplateView(await Html.PartialAsync("PartialViewName"));
      })
)

Expected/desired behavior

The EditorTemplateView() must accept Html.PartialAsync("PartialViewName").

Environment

• **Telerik UI for ASP.NET Core version: 2024.4.1112
• **Browser: [all]

[alestoya]

Conclusion

Closing this after further discussion. Such functionality would inevitably require introducing an asynchronous piece of logic within a synchronous method. This poses a risk in terms of how the underlying threading mechanism for the framework handles this situation.

Adding such a feature would inevitably place the UI thread in a predicament, as it may produce:

• Deadlocks
• Thread pool Exhaustion
• Impede the overall UX experience

There are several topics that discuss this in a more comprehensive manner:

• https://devblogs.microsoft.com/pfxteam/should-i-expose-synchronous-wrappers-for-asynchronous-methods
• https://blog.stephencleary.com/2017/03/aspnetcore-synchronization-context.html
• https://medium.com/rubrikkgroup/understanding-async-avoiding-deadlocks-e41f8f2c6f5d

Workaround

It is possible to use a code block, await the call to Html.PartialAsync and pass the result to the EditorTemplateView:

@{
    var myTemplate = await Html.PartialAsync("PartialViewName");
}

@(Html.Kendo().Form<UserViewModel>()
     .Name("myForm")
     .Items(items =>
     {
         items.Add().Field(f => f.Username).EditorTemplateView(myTemplate);
      })
)