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How do I make my method Input_Validating() more efficient? Input validation for a user

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I have a small Person Domain Model. As follows:

public class Person
{
 public Person()
 {
 FirstName = "John";
 LastName = "Doe";
 BirthDate = DateTime.Now.AddYears(-18);
 }
 [Key]
 [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
 public Guid PersonId { get; set; }
 [MaxLength(25, ErrorMessage = "The First Name cannot be more than 25 characters in length.")]
 [MinLength(3, ErrorMessage = "The First Name must be at least three characters.")]
 [Required(ErrorMessage = "The First Name is required.", AllowEmptyStrings = false)]
 [DisplayName("First Name")]
 public string FirstName { get; set; }
 [MaxLength(25, ErrorMessage = "The Last Name cannot be more than 25 characters in length.")]
 [MinLength(3, ErrorMessage = "The Last Name must be at least three characters in length.")]
 [Required(ErrorMessage = "The Last Name is required.", AllowEmptyStrings = false)]
 [DisplayName("Last Name")]
 public string LastName { get; set; }
 [DisplayName("Full Name")]
 public string FullName => string.Format("{0} {1}", FirstName, LastName);
 [Date(ErrorMessage = "Age must be between 18 and 65 years of age")]
 [DisplayName("Birth Date")]
 [DataType(DataType.Date,ErrorMessage = "This is not a valid date.")]
 [Required(ErrorMessage = "The Birth Date is Required")]
 public DateTime BirthDate { get; set; }
 [RegularExpression(@"^((?!000)(?!666)(?:[0-6]\d{2}|7[0-2][0-9]|73[0-3]|7[5-6][0-9]|77[0-2]))-((?!00)\d{2})-((?!0000)\d{4})$",
 ErrorMessage = "The Social Security Number must be in the pattern xxx-xx-xxx and be a valid US SSN.")]
 [DisplayName("Social Security #")]
 [Required(ErrorMessage = "The Social Security Number is Required.",AllowEmptyStrings = false)]
 public string SocialSecurityNumber { get; set; }
 public override string ToString()
 {
 return FullName;
 }
}

If I create a new MVC Web site and scaffold my controller, all my Validating Attributes just work on the create new and edit screens.

However, If I needed a WinForm to do the same thing, I would need to "roll my own". I did just that.

My WinForm code-behind in all its glory...

public partial class AddPersonForm : Form
{
 private readonly DemoContext _context;
 public AddPersonForm()
 {
 _context = new DemoContext();
 InitializeComponent();
 }
 protected override void OnLoad(EventArgs e)
 {
 _context.People.Load();
 personBindingSource.DataSource = _context.People.Local.ToBindingList();
 personBindingSource.RaiseListChangedEvents = true;
 FirstNameTextBox.Validating += Input_Validating;
 LastNameTextBox.Validating += Input_Validating;
 BirthDateDateTimePicker.Validating += Input_Validating;
 SocialSecurityNumberTextBox.Validating += Input_Validating;
 personBindingSource.AddNew();
 base.OnLoad(e);
 }
 private void personBindingNavigatorSaveItem_Click(object sender, EventArgs e)
 {
 personBindingSource.EndEdit();
 int changes = _context.SaveChanges();
 Debug.WriteLine("# of changes: " + changes);
 }
 private void Input_Validating(object sender, CancelEventArgs e)
 {
 // GetValidationErrors cannot see any errors unless the following line is present
 personBindingSource.EndEdit();
 IEnumerable<DbEntityValidationResult> results = _context.GetValidationErrors();
 foreach (DbEntityValidationResult result in results)
 {
 // Stops at the first error and also cancels the endedit.
 foreach (DbValidationError error in result.ValidationErrors)
 {
 Debug.WriteLine("Property: " + error.PropertyName);
 if (error.PropertyName == "FirstName")
 {
 errorProvider1.SetError(FirstNameTextBox, error.ErrorMessage);
 //e.Cancel = true;
 return;
 }
 if (error.PropertyName == "LastName")
 {
 errorProvider1.SetError(LastNameTextBox, error.ErrorMessage);
 //e.Cancel = true;
 return;
 }
 if (error.PropertyName == "BirthDate")
 {
 errorProvider1.SetError(BirthDateDateTimePicker, error.ErrorMessage);
 //e.Cancel = true;
 return;
 }
 if (error.PropertyName == "SocialSecurityNumber")
 {
 errorProvider1.SetError(SocialSecurityNumberTextBox, error.ErrorMessage);
 //e.Cancel = true;
 return;
 }
 }
 }
 errorProvider1.Clear();
 }
}

It may look bad, but it does work... How do I make my method Input_Validating() more efficient so I don’t have to write a new block for every input control on the form?