Question

By default, EF uses EntityObject when generating the objects. I’ve modified it to use my own AbstractEntityObject class. In doing so, I’ve added IValidatableObject as I was under the impression when you called context.SaveChanges() it would automatically call Validate and throw the exceptions.

Here is what I have:

public abstract class AbstractEntityObject : EntityObject, IValidatableObject
{
    private readonly DBTable table;

    protected AbstractEntityObject(DBTable table)
    {
        this.table = table;
    }

    public IEnumerable<ValidationResult> Validate(ValidationContext validationContext)
    {
        List<OITValidationResult> results = new List<OITValidationResult>();
        List<PropertyInfo> properties = new List<PropertyInfo>(GetType().GetProperties());

        foreach (DBField field in table.GetFields())
        {
            foreach (PropertyInfo prop in properties)
                if (StringUtilities.EqualsIgnoreCase(field.FieldName, prop.Name))
                {
                    results.AddRange(field.Validate(prop.GetValue(this, null)));
                    results.AddRange(AdditionalValidation(field, prop));
                    properties.Remove(prop);
                    break;
                }
        }

        return results;
    }

    public abstract List<OITValidationResult> AdditionalValidation(DBField field, PropertyInfo prop);
}

public abstract class AbstractTLMSEntityObject : AbstractEntityObject
{
    protected AbstractTLMSEntityObject(DBTable table) 
        : base(table)
    {
    }

    public override List<OITValidationResult> AdditionalValidation(DBField field, PropertyInfo prop)
    {
        List<OITValidationResult> results = new List<OITValidationResult>();

        if (!EntityState.Equals(EntityState.Unchanged))
        {
            if (StringUtilities.EqualsIgnoreCase(field.FieldName, "userid"))
                prop.SetValue(this, TLMSDB.User.UserName, null);
            else if (StringUtilities.EqualsIgnoreCase(prop.Name, "dtmod"))
                prop.SetValue(this, DateTime.Now, null);
        }

        OITValidationResult additionalResult = AdditionalValidation(field.Field);
        if (additionalResult != null)
            results.Add(additionalResult);

        return results;
    }

    /* By default there is no additional validation, subclasses should override this if they need additional validation */
    public virtual OITValidationResult AdditionalValidation(Enum field)
    {
        return null;
    }
}

Then, I have the subclass, which is a partial class along with the one that EF creates:

public partial class CSDCrud
{
    public enum Fields
    {
        RECEIPT_NUMBER,
        GRANT_ID,
        GRANT_FUND,
        TOTAL_ACRES
    }

    public CSDCrud() : base(CSDCrudDAO.Instance.Table)
    {
    }

    public static String GetDataPropertyName(Enum field)
    {
        return CSDCrudDAO.Instance.Table.GetField(field).FieldName;
    }
}

CSDCrud inherits from AbstractTLMSEntityObject thanks to me changing that in the .tt file.

Now here is where it gets weird. I have set it up so the DBField (referenced in the parent class) does self validation of the data. In this case, I have set it up so if receipt_number is required and thus will fail and throw an exception…In fact, the following occurs…

List<OITValidationResult> results = (List<OITValidationResult>)crudObject.Validate(null);
try
{
    CommonEntityManager.GetContext().CrudSet.AddObject(crudObject);
    CommonEntityManager.GetContext().SaveChanges();
    return true;
}
catch (Exception ex)
{
    return false;
}

As expected, results contains 1 item which is the proper error…however the SaveChanges saves it out just fine, without throwing an exception…what am I missing?

edit: I should note, obviously I can use the SavingChanges event to add in my own handler, but I’m hoping to use the pre-existing infrastructure.

static void context_SavingChanges(object sender, EventArgs e)
    {
        foreach (ObjectStateEntry ose in context.ObjectStateManager.GetObjectStateEntries(EntityState.Modified))
        {
            List<ValidationResult> results = new List<ValidationResult>(((IValidatableObject)ose.Entity).Validate(null));
            if (results.Count > 0)
                throw new CustomException(results);
        }

        foreach (ObjectStateEntry ose in context.ObjectStateManager.GetObjectStateEntries(EntityState.Added))
        {
            List<ValidationResult> results = new List<ValidationResult>(((IValidatableObject)ose.Entity).Validate(null));
            if (results.Count > 0)
                throw new CustomException(results);
        }
    }

Answer 1

Built-in validation is invoked only when you are using DbContext APIs and not ObjectContext APIs.