EditorFor on nullable DateTime - “Nullable object must have a value.”

Question

I am attempting to display a form that allows a user to input a new assignment for a person. I\'m using a DateTime.cshtml EditorTemplate to handle DateTime values for the a

Answer 1

create a DateTime.cshtml in your Shared/DisplayTemplate folder

@model Nullable<DateTime>
@(Model != null ? string.Format(ViewData.ModelMetadata.DisplayFormatString ?? "{0:d}", Model) : string.Empty)

this supports metadata from datannotations to be used if found.

Answer 2

UPDATE: GetValueOrDefault treats it as a DateTime and therefore the required Field validators are getting attached, because the original expression is for a datetime not a nullable datetime.

Therefore the solution below doesn't work.

Like the asker, I also used the DateTimeModelBinder from here: Here's the Link

This is how I solved a similar situation:

@Html.EditorFor(x => x.NewAssignment.AssignmentEndDate.GetValueOrDefault().Date)

And this is what my DateTime EditorTemplate looks like:

@model DateTime

@Html.TextBox("", Model != default(DateTime) ? Model.ToShortDateString() : String.Empty, new { @class = "datepicker", @maxlength = "10" })

Answer 3

The problem is that you're trying to retrieve the AssignmentEndDate.Value.Date, but AssignmentEndDate is null, which results in this error.

Since your editor template accepts a DateTime?, you should just pass along the AssignmentEndDate. In other words, remove the .Value.Date from the view:

@Html.EditorFor(x => x.NewAssignment.AssignmentEndDate, new { cssClass = "datePicker" })

Since your editor template is using ToShortDateString(), there's no need to "truncate" the time from the date at all.

Update

Regarding your desire to have separate "Date" and "Time" editors:

You can do this 2 ways.

1 - Your current DateTime? editor renders a field for the Model.Value.Date, so you could simply extend this to also render a field for the Model.Value.TimeOfDay. Example:

@{
  DateTime? modelDate = (Model == null) ? (DateTime?)null : Model.Value.Date;
  TimeSpan? modelTime = (Model == null) ? (TimeSpan?)null : Model.Value.TimeOfDay;
}
@Html.TextBox(..., modelDate, new{@class="datePicker"})
@Html.TextBox(..., modelTime, new{@class="timePicker"})

2 - You could split the above functionality into 2 separate editors, "DateOnly" and "TimeOnly". Then, update your view to call both editors:

@Html.EditorFor(x => x.NewAssignment.AssignmentEndDate, "DateOnly")
@Html.EditorFor(x => x.NewAssignment.AssignmentEndDate, "TimeOnly")

The choice is up to you, and whether you want to keep the Date and Time parts separate or together, but this is how I'd go about solving this problem.