MVC. Database value to ViewBag. Overloaded URL input choses whichValue to select

Question

This is my Controller code.

    public ActionResult Create(int? surveyGetter)
    {

        var survey = db.Surveys.FirstOrDefault(s => s.SurveyID == 1);
        if (survey != null){
            string question = survey.Question1;
            ViewBag.Question1 = question;
        }
        else if (survey == null) { ViewBag.Question1 = "Failed to retrieve Question from database."; }

        ViewBag.SurveyID = new SelectList(db.Surveys, "SurveyID", "SurveyName");

        return View();
    }

This example gets the database value of SurveyID == 1.

What I wish to do is let the input value surveyGetter replace the hardcoded 1, so that I can get the SurveyID value based on the surveyGetter value beening input.

Changing the 1 to surveyGetter gives null value.

Is this perhaps because of the FirstOrDefault expression? What expression must I change it to?

Answer 1

Answered by Daniel J.G.

How have you set your routes? If you are using the default {controller}/{action}/{id} then you have to rename surveyGetter as id.

Working code:

public ActionResult Create(int? id)
    {

        var survey = db.Surveys.FirstOrDefault(s => s.SurveyID == id);
        if (survey != null){
            string question = survey.Question1;
            ViewBag.Question1 = question;
        }
        else if (survey == null) { ViewBag.Question1 = "Failed to retrieve Question from database."; }

        ViewBag.SurveyID = new SelectList(db.Surveys, "SurveyID", "SurveyName");

        return View();
    }