CustomValidation attribute is not working with ASP.NET MVC 3 and EF
Question
I understood how to create custom validation attributes. In fact, the Validate method is being execute when I use the Seed method to pre-populate the database, and if it fails it throws an exception. However, the validation is not working on the Create Form of the entity.
Do I have to change something to the HTML (Razor Form)?
It just lets me add items that fail the validation.
Code here:
namespace Data.Model
{
[AttributeUsage(AttributeTargets.Property | AttributeTargets.Field, AllowMultiple = false)]
sealed public class YearsValidationAttribute : ValidationAttribute
{
// Internal field to hold the min value.
readonly int _years;
public int Years
{
get { return _years; }
}
public YearsValidationAttribute(int years)
{
_years = years;
}
public override bool IsValid(object value)
{
var years = (int)value;
bool result = true;
if (this.Years != null)
{
result = Years >= years;
}
return result;
}
public override string FormatErrorMessage(string name)
{
return String.Format(CultureInfo.CurrentCulture,
ErrorMessageString, name, Years);
}
}
}
public class Position
{
[DatabaseGenerated(System.ComponentModel.DataAnnotations.DatabaseGeneratedOption.Identity)]
public int PositionID { get; set; }
[Required(ErrorMessage = "Position name is required.")]
[StringLength(20, MinimumLength = 3, ErrorMessage = "Name should not be longer than 20 characters.")]
[Display(Name = "Position name")]
public string name { get; set; }
[Required(ErrorMessage = "Number of years is required")]
[Display(Name = "Number of years")]
[YearsValidationAttribute(5, ErrorMessage = "{0} value must be greater than {1} years.")]
public int yearsExperienceRequired { get; set; }
public virtual ICollection<ApplicantPosition> applicantPosition { get; set; }
}
@using (Html.BeginForm()) {
@Html.ValidationSummary(true)
<fieldset>
<legend>Position</legend>
@Html.HiddenFor(model => model.PositionID)
<div class="editor-label">
@Html.LabelFor(model => model.name)
</div>
<div class="editor-field">
@Html.EditorFor(model => model.name)
@Html.ValidationMessageFor(model => model.name)
</div>
<div class="editor-label">
@Html.LabelFor(model => model.yearsExperienceRequired)
</div>
<div class="editor-field">
@Html.EditorFor(model => model.yearsExperienceRequired)
@Html.ValidationMessageFor(model => model.yearsExperienceRequired)
</div>
<p>
<input type="submit" value="Save" />
</p>
</fieldset>
}
Solution
That code you have won't give you a client validator, only the server side. But that is a good starting point. What you need to do in your action method on the server is to check if the model is valid like such:
public ActionResult YourAction(YourModel model)
{
if(ModelState.IsValid)
{
// Do your save
}
else
{
// Do your other stuff
}
}
If you want client side validation as well you can use the resources here: http://bradwilson.typepad.com/blog/2010/10/mvc3-unobtrusive-validation.html
You can also try to use the Remote
validation attribute: http://msdn.microsoft.com/en-us/library/gg508808(v=vs.98).aspx