How To Bind Model Value From Body by Custom Binder

[Eilon]

From @Edward-Zhou on July 18, 2018 9:33

I am trying this document Custom Model Binding in ASP.NET Core, I could get the model value when passing by Query String.
But, I want to bind the model to Request Body, how could I fetch value from Request body when I sending request with application/json.

Copied from original issue: dotnet/aspnetcore#3338

[mkArtakMSFT]

Hi @Edward-Zhou. It looks like this is a question about how to use ASP.NET Core. While we do our best to look through all the issues filed here, to get a faster response we suggest posting your questions to StackOverflow using the asp.net-core-mvc tag.

[mkArtakMSFT]

/cc @dougbu

[Edward-Zhou]

Before asking in StackOverflow, I am wondering whether my requirement is possible. I already researched in StackOverflow, but did not find any related information about this.

[dougbu]

@Edward-Zhou one option is to write CustomModelBinder as a wrapper around the existing BodyModelBinder. The wrapper could change property values, map the returned model to something different, et cetera. (A few of the built-in binders e.g. CollectionModelBinder and ComplexTypeModelBinder use inner model binders. See also the corresponding IModelBinderProvider implementations e.g. CollectionModelBinderProvider.)

Another possibility is to rewrite BodyModelBinder in your CustomModelBinder, adding or removing whatever you need. If you take this approach, I'll be interested to hear your reasons.

Might also wrap BodyModelBinder to make it more "something" in CustomModelBinder. I doubt this would be valuable in this context. But, I did this in aspnet/WebHooks. (The "something" there was mainly usability in request filters.) See the WebHookRequestReader in that repo.

[mkArtakMSFT]

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