How to automatically add placeholder attribute to html input type number in mvc 4?

Question

This is a very specific issue. I managed to automatically add the placeholder attribute to html5 email input type by using an editor template called EmailAddress.cshtml

Answer 1

Based on Pat Burke comment, I can use the UIHint data attribute combined with the good editor template.

Here is an example (Editor Template):

@Html.TextBox("", ViewData.TemplateInfo.FormattedModelValue, new { @class = "text-box single-line", placeholder = ViewData.ModelMetadata.Watermark, type = "number" })

(the ViewModel)

public class MiageQuotaRequestViewModel
{
    [Required]
    [UIHint("Number")]
    [DataType(DataType.EmailAddress)]
    [Display(Name = "Nombre de place demandées", Prompt = "Nombre de place")]
    [Range(0, 50, ErrorMessage = "La demande doit être comprise entre 0 et 50 places")]
    public int? RequestedQuota { get; set; }
}

and finally the result: