best way to persist data in .NET Web Service

Question

I have a web service that queries data from this json file, but I don't want the web service to have to access the file every time. I'm thinking that maybe I can store the data somewhere else (maybe in memory) so the web service can just get the data from there the next time it's trying to query the same data. I kinda understand what needs to be done but I'm just not sure how to actually do it. How do we persist data in a web service?

Update: Both suggestions, caching and using static variables, look good. Maybe I should just use both so I can look at one first, and if it's not in there, use the second one, if it's not in there either, then I'll look at the json file.

Answer 1

Extending on Ice^^Heat's idea, you might want to think about where you would cache - either cache the contents of the json file in the Application cache like so:

Context.Cache.Insert("foo", _
                 Foo, _
                 Nothing, _
                 DateAdd(DateInterval.Minute, 30, Now()), _
                 System.Web.Caching.Cache.NoSlidingExpiration)

And then generate the results you need from that on every hit. Alternatively you can cache the webservice output on the function definition:

<WebMethod(CacheDuration:=60)> _
Public Function HelloWorld() As String
    Return "Hello World"
End Function

Info gathered from XML Web Service Caching Strategies.