默认情况下，EF 在生成对象时使用 EntityObject。我已经修改它以使用我自己的 AbstractEntityObject 类。这样做时，我添加了 IValidatableObject，因为当您调用 context.SaveChanges() 时，我的印象是它会自动调用 Validate 并抛出异常。
这是我所拥有的：
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;
}
}
然后，我有了子类，它是部分类以及 EF 创建的子类：
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;
}
}
由于我在 .tt 文件中更改了它，CSDCrud 继承自 AbstractTLMSEntityObject。
现在这是变得奇怪的地方。我已经对其进行了设置，以便 DBField（在父类中引用）对数据进行自我验证。在这种情况下，我已经设置了它，所以如果需要receipt_number，因此会失败并抛出异常......事实上，会发生以下情况......
List<OITValidationResult> results = (List<OITValidationResult>)crudObject.Validate(null);
try
{
CommonEntityManager.GetContext().CrudSet.AddObject(crudObject);
CommonEntityManager.GetContext().SaveChanges();
return true;
}
catch (Exception ex)
{
return false;
}
正如预期的那样，结果包含 1 项是正确的错误...但是 SaveChanges 将其保存得很好，不会引发异常...我错过了什么？
编辑：我应该注意，显然我可以使用 SavingChanges 事件来添加我自己的处理程序，但我希望使用预先存在的基础设施。
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);
}
}