title: handle multiple request of REST API
body: <p>I have create a rest api using api Controller in ASP.NET and performing some task that may take 10 minutes to finish task because user enter the time to finish that task. In this case  I think multiple request can't be handle.</p>
  
  <p>I am using this --</p>
  
  <pre><code> public class Controller : ApiController
      {
       [HttpGet]
          [ActionName("APICall")]
          public string API()
          {
  
              Rest y = new Rest();
              return y.APiDATA();
          }
  
  }
  </code></pre>
  
  <p>my question is during performing this task when one more request come then does it create new thread for each request or not? if not then how to handle concurrent request .
  Please help me.</p>
  
  <pre><code>I am getting following error when calling url after deploy in IIS 
  </code></pre>
  
  <p>{"Message":"An error has occurred.","ExceptionMessage":"Object reference not set to an instance of an object.","ExceptionType":"System.NullReferenceException","St‌​ackTrace":" at restapi.service.Rest.synthetic()\r\n at lambda_method(Closure , Object , Object[] )\r\n at System.Web.Http.Controllers.ReflectedHttpActionDescriptor.Ac‌​tionExecutor.&lt;>c__Di‌​splayClass13.b__c(Ob‌​ject instance, Object[] methodParameters)\r\n at System.Threading.Tasks.TaskHelpers.RunSynchronously[TResult]‌​(Func`1 func, CancellationToken cancellationToken)"}</p>