How to get Form Collected values from a View to FileStreamResult function in Controller

Question

I have a webpage on which there are two drop down list selections. On submitting the page loads with a PDF viewer I've implemented using HTML object tag. Now the object tag calls the function on the controller to load the PDF file.

Code of the View:

<object data="@Url.Action("GetPDF")" type="application/pdf" width="100%" height="500"></object>

My controller:

  public FileStreamResult GetPDF()
    {
      FileStream fs = new FileStream("C:/Users/ABC/Desktop/Office/Resources/Resources/HRDocs/2017/May/2017-MAY-1887CJODU5VKJM.pdf", FileMode.Open, FileAccess.Read);
        return File(fs, "application/pdf");
    }

FileStream link is static and I want to make it dynamic by:

     public FileStreamResult GetPDF(HRModel objHR)
    {
        string UserName = User.Identity.Name.ToString();
        string SelectedYr = Convert.ToString(objHR.SelectedYear);
        int SelectedMonth = Convert.ToInt32(objHR.SelectedMonthId);
        string MonthName = dbContext.EmployeeSalaries.Where(f => f.MonthId == objHR.SelectedMonthId).FirstOrDefault().Month;
        var SalLink = dbContext.EmployeeSalaries.FirstOrDefault(a => a.MonthId == SelectedMonth && a.Year == SelectedYr && a.UserName == UserName);

      FileStream fs = new FileStream(Server.MapPath(string.Format("~/HRDocs/{0}/{1}/{2}", objHR.SelectedYear, MonthName, SalLink.URL)), FileMode.Open, FileAccess.Read);
        return File(fs, "application/pdf");
    }

As I want to retrieve a specific file based on the selection from the dropdown lists, I've parameterized the function with Model with values from the View. But the Model's object doesn't capture any values.

I also use an ActionResult Submit which brings the form collected values to the controller:

    [HttpPost]
    public ActionResult Submit(FormCollection frmCollection, HRModel objHR)
    {

        try
        {
            string UserName = User.Identity.Name.ToString();
                ViewBag.UserId = User.Identity.Name.ToString();
                objHR.YearList = dbContext.EmployeeSalaries.Where(f => f.UserName == UserName).GroupBy(f => f.Year).Select(g => g.FirstOrDefault()).ToList();
                objHR.MonthList = dbContext.EmployeeSalaries.Where(f => f.UserName == UserName).GroupBy(f => f.MonthId).Select(g => g.FirstOrDefault()).ToList();
                string SelectedYr = Convert.ToString(objHR.SelectedYear);
                int SelectedMonth = Convert.ToInt32(objHR.SelectedMonthId);
                string MonthName = dbContext.EmployeeSalaries.Where(f => f.MonthId == objHR.SelectedMonthId).FirstOrDefault().Month;
                var SyncDate = dbContext.EmployeeSalaries.FirstOrDefault(a => a.MonthId == SelectedMonth && a.Year == SelectedYr && a.UserName == UserName);
                objHR.SyncDate = Convert.ToDateTime(SyncDate.SyncDate);
                var SalLink = dbContext.EmployeeSalaries.FirstOrDefault(a => a.MonthId == SelectedMonth && a.Year == SelectedYr && a.UserName == UserName);
                if (SalLink == null)
                {
                    ViewBag.Empty = "true";
                }
                else
                {
                    ViewBag.Links = string.Format("/HRDocs/{0}/{1}/{2}", objHR.SelectedYear, MonthName, SalLink.URL);
                    objHR.URL = SalLink.URL;
                    ViewBag.IsValid = "true";
                }
                return View(objHR);
            }

How can I bring user selected values to the GetPDF function?

score 0 · Answer 1 · answered Jun 15 '17 at 08:13

You'll have to realise that the request that renders the page and the request that obtains the PDF to render on that page are two separate requests.

So this should just work, granted that you pass the appropriate parameters to the @Url.Action():

<object data="@Url.Action("GetPDF", new { SelectedYear = "2017", SelectedMonthId = "6" })" ... />

Then the HRModel model parameter of GetPDF() will bind from the query string of that action.

If you want to alter the URL at the client side when the dropdowns change, then that's an entirely different question altogether. See for example ASP.net mvc Call Action on DropDown Value Change.

How to get Form Collected values from a View to FileStreamResult function in Controller

1 Answers1