Exception Filter

Filter Types

• Authorization filters
• Resources filters (run right after the authorization filters and useful for caching and performance)
• Action filters (run right before and after the action method)
• Exception filters (to handle the exceptions before the response body is populated)
• Result filters (run before and after the execution of the action methods result)

Create Exp filter

• In the "Exceptions" Folder create another Folder named "Filters":

CustomExceptionFilter.cs

[AttributeUsage(AttributeTargets.Class | AttributeRargets.Method)] 
public class CustomExceptionFilter : ExceptionFilterAttribute
{
  public override void OnException(ExceptionContext context)
  {
    context.HttpContext.Response.ContentType = "application/json";
    var statusCode = HttpStatusCode.InternalServerError;
    if(context.Exception is TestException)
    {
      statusCode = HttpStatusCode.NotFound;
    }
    var expString = new ErrorResponseData()
    {
      StatusCode = (int)stausCode,
      Message = context.Exception.Message,
      Path = context.Exception.StackTrace
    };
    context.Result = new JsonResult(expString);
  }
}

Use Exp filter

• Just use as an "Attribute" on top of each method in the controller for example.