Question

I wonder how can I cache webservice returned data by its passed argument?

For example:

[WebMethod]
[ScriptMethod(ResponseFormat = ResponseFormat.Json)]
public string FunctionThatReturnsSomething(int param1){
   ... does something
return strResult;

}

What I want is that the returned the webservice returned data will be cached, but according to the parameter value (inr param1). So if, for example, the webservice function gets a value of ‘1’, it will cache the results for that. If the functions gets ‘2’ integer for the param1, it will cache another result.

note: the webmethod/webservice is being called via Ajax call using POST method.

Answer 1

ASP.NET handily provides the Application Cache just for this sort of thing.

In it’s simplest form, you can just add data to the cache like this:

HttpRuntime.Cache["Key"] = "Value"; 

So you could cache the data that you want to return easily:

string cacheKey = "FunctionThatReturnsSomething_" + param1.ToString();

if (HttpRuntime.Cache[cacheKey] == null)
{
    string myData = GetDataToReturn(param1);

    HttpRuntime.Cache[cacheKey] = myData; 
}

return (string)HttpRuntime.Cache[cacheKey];

It also allows you to specify a CacheDependancy. So for example if your data was based on a local file, you can have the cache automatically cleared if that file is updated.

You can also have data that you enter into the cache removed after a certain time, for example if it hasn’t been used for 10 minutes:

HttpRuntime.Cache.Insert(cacheKey, myData, null, System.Web.Caching.Cache.NoAbsoluteExpiration, new TimeSpan(0, 10, 0));

Or at an absolute time, such as 10 minutes after you add it:

HttpRuntime.Cache.Insert(cacheKey, myData, null, DateTime.Now.AddMinutes(10), 
System.Web.Caching.Cache.NoSlidingExpiration);