MVC Controller parameters not required but optional

Question

Hi I'm using a HttpPost from a view to send some parameters to a controller, the db gets filtered according to those given parameters. BUT the parameters should be optional and if not given the controller just ignores them. But this seems to be impossible?

VIEW

@using (Html.BeginForm("Index", "Logbook")) {
 @Html.ValidationSummary(true)
       <div class="col-lg-3">
           <div class="panel panel-default">
               <div class="panel-heading">
                   <i class="fa fa-bell fa-fw"></i> Filter logbook
               </div>
               <div class="panel-body">
                   <div class="col-lg-5">
                        @Html.Label("Filter on room: ")
                        @Html.Label("Filter on date: ")
                   </div>
                   <div class="col-lg-6"> 
                        @Html.DropDownList("dropdownlist",Eindwerk.Controllers.RoomController.GetRooms(),new { @class = "btn btn-default-dropdown-toggle"})
                        @Html.TextBox("datepicker","", new { @class = "form-control" })
                   </div>
                <div>
                <button type="submit" class="btn btn-outline btn-primary btn-lg btn-block">Filter logbook</button>
                @Html.ActionLink("Remove Filter", "Index","FilterClear",new { @class = "btn btn-outline btn-success btn-lg btn-block" })
           </div>

}

CONTROLLER

I thought it would be possible to just check if the parameter was null or not and change the function accordingly:

[HttpPost]
public ActionResult Index(string dropdownlist, DateTime datepicker)
{
    if(dropdownlist != null && datepicker != null)
    return View(db.Logbook.Where(p => p.Room == dropdownlist && p.Time.Day == datepicker.Month).OrderByDescending(a => a.Id).ToList());

    if(dropdownlist != null && datepicker == null)
    return View(db.Logbook.Where(p => p.Room == dropdownlist).OrderByDescending(a => a.Id).ToList());

    if(dropdownlist == null && datepicker != null)
    return View(db.Logbook.Where(p => p.Time.Day == datepicker.Month).OrderByDescending(a => a.Id).ToList());

    else
    return View(db.Logbook.OrderByDescending(p => p.Id).ToList());

}

But I get an instant error that the parameters should be given, is there a possibility to set these parameters to optional?

Indeed, so easy but didn't think of it. Thanks! Can't accept as answer though it's a comment... — user3629755
– user3629755, Commented Jun 11, 2014 at 11:55

user3559349 · Accepted Answer · 2014-06-11 12:03:39Z

2

Declare the parameter as nullable

public ActionResult Index(string dropdownlist, DateTime? datepicker)

answered Jun 11, 2014 at 12:03

user3559349

Sign up to request clarification or add additional context in comments.

Comments

Sefa · Accepted Answer · 2014-06-11 11:53:57Z

0

declare nullable parameters

public ActionResult Index(string? dropdownlist, DateTime? datepicker)

answered Jun 11, 2014 at 11:53

Sefa

9,00010 gold badges54 silver badges85 bronze badges

2 Comments

user3629755 Over a year ago

As Stephen Muecke already said: the solution was to set DateTime? datepicker as nullable. On string this doesn't have to cause string can be null. thanks anyway!

Dismissile Over a year ago

You can't have a string? parameter. String is already "nullable" by default.

Amol Shiledar · Accepted Answer · 2014-06-11 19:25:18Z

0

try this it can be work

public ActionResult Index(string dropdownlist=null, DateTime datepicker=null)

answered Jun 11, 2014 at 19:25

Amol Shiledar

4034 silver badges13 bronze badges

Comments

JTW · Accepted Answer · 2014-06-12 11:55:22Z

0

You can remedy this by making the parameter optional and assigning a default value of null:

public ActionResult Index(string dropdownlist, DateTime? datepicker = null){}

edited Jun 12, 2014 at 11:55

answered Jun 11, 2014 at 12:01

JTW

3,7758 gold badges38 silver badges50 bronze badges

Collectives™ on Stack Overflow

MVC Controller parameters not required but optional

4 Answers 4

Comments

2 Comments

Comments

Comments

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

Comments

2 Comments

Comments

Comments

Related