Receive null int in Razor (@Html.Textboxfor)

Question

I have an object Carro and I have a whole-type, annulable property called AnoInspecao. When creating, I can create a car object with the year of null inspection (without typing anything) and persist in the bank normally.

var carro = new Carro()
{
   carro.AnoInspecao = null;
   carro.Nome = "meuCarro"
}

When it’s time to edit (View), I use the following code:

@Html.TexboxFor(model => model.AnoInspecao)

But it doesn’t work, because the Textbox does not accept null, thus generating a Exception.

How can I treat that?

Answer 1

Simple, do not pass null to the TextBox.

@Html.TexboxFor(model => model.AnoInspecao ?? "")

or

@Html.TexboxFor(model => model.AnoInspecao != null ? model.AnoInspecao.ToString() : "")

The operator ?? is called null-coalescing. It validates what you have on the left and if it is null makes the value sent be the one coming from the right side.

Related: What is the meaning of the operator "??"

Answer 2

Another way is by using the following:

@Html.TextBoxFor(model => model.AnoInspecao, new { Value = "", @type = "number" })

Apart from the @type, this solution works for everything Nullable.