Asp.net Web API - return data from actionfilter

Question

I want to return a json object from the wep api actionfilter. How can I achieve this?

I can return the object from action but I need to return some data from the actionf

Answer 1

All you need is to assign the Response:

public class MyActionFilterAttribute: ActionFilterAttribute
{
    public override void OnActionExecuting(HttpActionContext actionContext)
    {
        actionContext.Response = actionContext.Request.CreateResponse(
            HttpStatusCode.OK, 
            new { foo = "bar" }, 
            actionContext.ControllerContext.Configuration.Formatters.JsonFormatter
        );
    }
}

Assuming the following controller action:

[MyActionFilter]
public string Get()
{
    return "OK";
}

this custom action filter will short-circuit the execution of the action and directly return the response we provided.