具有DateTime元素的类型化XML列-DateTime被转换

Question

I have a typed XML column in which I store the serialization from a C# object with a DateTime property. That DateTime is of Local type when I store it in the DB - although the serialized XML shows the time with an offset to GT time, as in '2009-09-22T13:52:32.2346252-07:00' (I live in Oregon). When I read the table (from within the SQL Management Studio), the XML shows the DateTime object in UTC type. Is there a way to control this behavior? It is important to me to respect the timezone of the data I put in, since it can come from different sources, and I need to respect that when I pull it out. I also do not want to convert every date time field from UTC to local after I read the objects from the DB.

this is the C# definition of the object I store:

[Serializable]
[XmlType(Namespace="urn://MySchema")]
public class MyObject
{
    public DateTime RecordTime { get; set; }
    // .. omitted for clarity
}

This is the definition of the table (simplified for clarity)

CREATE TABLE MyTable(
    [ID] [int] IDENTITY(1,1) NOT NULL,
    [MyKey] [int] NULL,
    [TheObject] [xml](CONTENT [dbo].[MySchema]) NULL,
 CONSTRAINT [PK_MyTable] PRIMARY KEY CLUSTERED 
(
    [ID] ASC
)WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, IGNORE_DUP_KEY = OFF,       ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY]
) ON [PRIMARY]

This is how my sproc looks like (also simplified)

ALTER PROCEDURE [dbo].[SaveMyObjects] 
    @where int, 
    @object xml
AS
BEGIN
INSERT INTO MyTable
    (MyKey, TheObject)
    VALUES(@where, @object)
END

I need to do 2 things differently:

1. I want to control the format of the date string in the serialized XML - I'd prefer an ISO format for that time string
2. I do not want to the DateTime to be converted to UTC when I store it in the DB, but I'd like the convenience of keeping it as a DateTime field.

How do I do that? Any idea, pointer, link to some god's blog showing my my errors, etc.. would be much appreciated.

Answer 1

Not the cleanest way to do it, but you could do something like this:

[Serializable]
[XmlType(Namespace="urn://MySchema")]
public class MyObject
{
    [XmlIgnore]
    public DateTime RecordTime { get; set; }

    //property for serialization purposes
    [XmlElement(ElementName="RecordTime")]
    public string XmlRecordTime
    {
        get { return this.RecordTime.ToString("o"); }
        set { this.RecordTime = new DateTime.Parse(value); }
    }
}

Also, take a look at XmlAttributeOverrides class - more work, but cleaner.

Answer 2

是否可以使用DateTimeOffset代替DateTime？