"Microsoft.AspNetCore.Mvc.ViewFeatures.Internal" can not find in dotnet core 3.0.0-preview7-27912-14

[Benknightdark]

After I upgrade my dotnet core 2.2 MVC application to 3.0.0-preview7-27912-14, my custom razor html extesion can not find "Microsoft.AspNetCore.Mvc.ViewFeatures.Internal".

And, after "Microsoft.AspNetCore.Mvc.ViewFeatures.Internal" can not find , here is some function I can not use , such as ExpressionHelper and ExpressionMetadataProvider.

Here is my example github url : https://github.com/Benknightdark/dotnetcore3v7

[davidfowl]

We've moved all pubternal APIs to be truly internal. #4932

You'll need to copy that code over to your project from MVC.

cc @pranavkm @rynowak

[rynowak]

@pranavkm - did we create a public version of these APIs?

[pranavkm]

From #8678 (comment)

We addressed this particular gap as part of aspnet/Mvc#8724. 3.0 offers a ModelExpressionProvider type that's available from DI and combines the 3 APIs that were previously available:

• ModelExpressionProvider.GetExpressionText<TModel, TValue>(Expression<Func<TModel, TValue>>)
• ModelExpressionProvider.CreateModelExpression<TModel, TValue>(ViewDataDictionary<TModel>, string expression)
• ModelExpressionProvider.CreateModelExpression<TModel, TValue>(ViewDataDictionary<TModel>, Expression<Func<TModel, TValue>> expression)

The latter two return an instance of ModelExpression which is a superset for ModelExplorer that ExpressionMetadataProvider returns. aspnet/Mvc#8724 (comment) has a suggestion for libraries that need to support different versions of AspNetCore.

[Benknightdark]

OK, thanks for your help