David M的建議和文章鏈接很棒。萬一別人有前往該網站,但問題(我不得不從谷歌緩存加載它),這裏是我的解決方案:
public abstract class BaseImmutableUserType : IUserType
{
public abstract object NullSafeGet(IDataReader rs, string[] names, object owner);
public abstract void NullSafeSet(IDbCommand cmd, object value, int index);
public abstract SqlType[] SqlTypes { get; }
public new bool Equals(object x, object y)
{
if (ReferenceEquals(x, y))
{
return true;
}
if (x == null || y == null)
{
return false;
}
return x.Equals(y);
}
public int GetHashCode(object x)
{
return x.GetHashCode();
}
public object DeepCopy(object value)
{
return value;
}
public object Replace(object original, object target, object owner)
{
return original;
}
public object Assemble(object cached, object owner)
{
return DeepCopy(cached);
}
public object Disassemble(object value)
{
return DeepCopy(value);
}
public Type ReturnedType
{
get { return typeof(T); }
}
public bool IsMutable
{
get { return false; }
}
}
public class VersionUserType: BaseImmutableUserType
{
public override SqlType[] SqlTypes
{
get
{
return new SqlType[]{new StringSqlType()};
}
}
public override object NullSafeGet(IDataReader rs, string[] names, object owner)
{
Version version = null;
var value = NHibernateUtil.String.NullSafeGet(rs, names) as string;
if (value != null)
version = new Version(value);
return version;
}
public override void NullSafeSet(IDbCommand cmd, object value, int index)
{
object valueToSet;
Version version = value as Version;
if (version != null)
{
valueToSet = version.ToString();
}
else
{
valueToSet = DBNull.Value;
}
NHibernateUtil.String.NullSafeSet(cmd, valueToSet, index);
}
}
和映射文件現在有此屬性:
<屬性名= 「MyVersion」 列= 「MyVersion」 不空= 「真」 TYPE = 「My.Namespace.VersionUserType,My.Assembly」/ >
這正是我以前在我的代碼中所做的,效果很好。 – 2010-01-05 17:02:45
我在許多其他情況下做過,但沒有版本。如果你已經工作的代碼,你可能想發佈一個與它的答案... – 2010-01-05 17:07:12
該URL沒有響應。任何人都有它的緩存版本? – 2010-01-05 17:15:09