How do I know what reference to include to import a specific .NET namespace?

Question

This is in reference to a problem I had which I was able to find the solution to here on SO.

This wasn't my question, but it was the same exact problem I had. How do I know that I need to import a specific DLL to use a specific namespace? I saw no reference to this on either the MSDN page or the Object Explorer, and even Resharper didn't pick up on it. Is this referenced anywhere?

Answer 1

From http://msdn.microsoft.com/en-us/library/system.runtime.serialization.json.datacontractjsonserializer.aspx:

DataContractJsonSerializer Class

Serializes objects to the JavaScript Object Notation (JSON) and deserializes JSON data to objects. This class cannot be inherited.

Namespace: System.Runtime.Serialization.Json
Assembly: System.ServiceModel.Web (in System.ServiceModel.Web.dll)

Answer 2

Good question. I generally do a quick search for the class on Google, then start typing for the assembly based on the beginning of the namespace it's in.

Answer 3

When you look up the namespace on MSDN, most classes specify the assembly where it resides.

In reference to your previous question: MSDN Reference

Near the top you get your answer:

Namespace:  System.Runtime.Serialization.Json
Assembly:  System.ServiceModel.Web (in System.ServiceModel.Web.dll)