Hi,
In Swagger Ui parameters show what are all parameter available in controller action.

Like this. here guid data type shows like string at same date time data type also shows undefined. If give (Guid?) and (DataTime?) it will show right data type. can you pls guid me what I need to do.
In function I need to give (Guid) this data type only not (Guid?). Kindly help me.
Help me regarding this issue?
I'm afraid I don't understand what your asking. Maybe you could provide some examples?
Closing due to inactivity - as far as I can see the generated docs for Guid's and DataTime (and the nullable variants) are correct. So, if you want to re-open, you'll have to provide more detail.
Maybe what's meant here is that if I define an API operation (web API method) that takes a Guid as parameter, the "parameters" documentation section shows it being "Data Type: string" (and not Guid) like illustrated in the picture. I'm seeing this too with Swashbuckle 5.2.1. Maybe this is intentional as Guid is pretty much a .NET specific concept and would not mean much for callers using other languages?
Having better support for the format parameters would be great in my opinion. In order to generate useful proxies, we need a way to distinguish Guids from regular strings. The swagger specification states (under "Data Types") that you can use custom strings for formats. They even list "uuid" in one of there examples. Although i prefer the term "guid" it seems like the more platform agnostic term is "uuid" so I'd be fine with that as well.
Of course, supporting the date / datetime formats is equally important in my opinion.
Most helpful comment
Maybe what's meant here is that if I define an API operation (web API method) that takes a Guid as parameter, the "parameters" documentation section shows it being "Data Type: string" (and not Guid) like illustrated in the picture. I'm seeing this too with Swashbuckle 5.2.1. Maybe this is intentional as Guid is pretty much a .NET specific concept and would not mean much for callers using other languages?