如何在asp.net核心的ActionFilter中刷新响应？

Question

I am trying to delete a file that is dynamically generated at my controller using an ActionFilter.

public class DeleteFileAttribute : ActionFilterAttribute {
    public override void OnActionExecuted(ActionExecutedContext context) {
        /* MVC 4 code which worked just fine
        context.HttpContext.Response.Flush();

        var filePathResult = context.Result as FilePathResult;

        if(filePathResult!=null){
            File.Delete(filePathResult.FileName);
        }
        End of MVC 4 code */

        // I am not able to flush response as context.HttpContext.Response does not have a Flush method
        var vb = (context.Controller as Controller).ViewBag;
        string fileToDelete = vb.FileToDelete;

        if(File.Exists(fileToDelete)) {
            // ERROR: Process cannot access the file ... because it is being used by another process
            File.Delete(fileToDelete);
        }
    }
}

As mentioned in the code comment, since I am not able to flush the response and then delete the file I get IOException: The process cannot access the file ... because it is being used by another process exception.

What is a sure way to delete the file in the action filter after the user has finished downloading it?

Answer 1

Using OnResultExecuted event instead of OnActionExecuted in the action filter solved the issue. No flushing of Response is needed.