1. ActionResult

ViewResult 返回响应的视图

ContentResult 返回字符串

public ActionResult Content()
{
    return Content("Content");
}

RedirectResult 重定向

RedirectToRouteResult 根据路由重定向

FileContentResult 文件内容

public ActionResult GetPhoto(string fileName)
{
    if (string.IsNullOrEmpty(fileName))
    {
        return Content(nameof(fileName) + "为空！");
    }
    return File("~/Uploads/" + fileName, "image/jpg");
}
public ActionResult UploadPhoto()
{
    return View();
}
[HttpPost]
public ActionResult UploadPhoto(HttpPostedFileBase file)
{
    string fileName = $"{DateTime.Now.Ticks}.{file.FileName.Split('.').Last()}";
    string savePath = "~/Uploads/" + fileName;
    file.SaveAs(Request.MapPath(savePath));
    return Content(fileName);
}

JsonResult 返回Json数据

HttpStatusCodeResult 状态码

PartialViewResult 分部视图页面，类似于组件

Http.Action()
Html.Partial()