序列化UTC时间c#

时间:2015-12-08 23:02:20

标签: c# datetime string-formatting datacontractserializer

我在datacontract中有一个DateTime数据库。默认情况下,datacontractserializer将UTC时间序列化为yyyy-MM-ddTHH:mm:ss.fffffffZ格式。我需要yyyy-MM-ddTHH:mm:ss.000Z格式,但无法控制数据交换。那么我可以用DataContractSerializer做什么,它会以我想要的格式给我UTC时间。谢谢

1 个答案:

答案 0 :(得分:4)

我创建了一个实现,它使用IDataContractSurrogate的实现来使用您拥有的DTO序列化DTO。

DTO的

你没有提供DTO,所以我创建了一个作为你的原始DTO(你无法改变)和我们拥有的一个替代DTO。除了DateTime属性更改为String类型外,它们将具有相同的公共签名。

/// <summary>
/// original DTO, is fixed
/// </summary>
[DataContract]
class DTO
{
    [DataMember]
    public DateTime FirstDate { get; set; }

}

/// <summary>
/// Our own DTO, will act as surrogate
/// </summary>
[DataContract(Name="DTO")]
class DTO_UTC
{
    [DataMember]
    public string FirstDate { get; set; }
}

IDataContractSurrogate

IDataContractSurrogate提供了在序列化和反序列化期间将一种类型替换为另一种类型所需的方法。

我在这里使用了简单的反思。如果需要更好的性能,请考虑在类型之间发出生成的代码,甚至生成目标类型。

public class DTOTypeSurrogate : IDataContractSurrogate
{
    // this determines how you want to replace one type with the other
    public Type GetDataContractType(Type type)
    {
        if (type == typeof(DTO))
        {
            return typeof(DTO_UTC);
        }
        return type;
    }

    public object GetDeserializedObject(object obj, Type targetType)
    {
        // do we know this type
        if (targetType == typeof(DTO))
        {
            // find each DateTime prop and copy over
            var objType = obj.GetType();
            var target = Activator.CreateInstance(targetType);
            foreach(var prop in targetType.GetProperties())
            {
                // value comes in
                var src =  objType.GetProperty(prop.Name);
                // do we need special handling
                if (prop.PropertyType == typeof(DateTime))
                {
                    DateTime utcConvert;
                    // parse to a datetime
                    if (DateTime.TryParse(
                        (string) src.GetValue(obj),
                        System.Globalization.CultureInfo.InvariantCulture, 
                        System.Globalization.DateTimeStyles.AdjustToUniversal, 
                        out utcConvert))
                    {
                        // store 
                        prop.SetValue(target, utcConvert);
                    }
                }
                else
                {
                    // store non DateTime types
                    prop.SetValue(target, src);
                }
            }
            return target;
        }
        return obj;
    }

    public object GetObjectToSerialize(object obj, Type targetType)
    {
        // go from DTO to DTO_UTC
        if (targetType == typeof(DTO_UTC))
        {
            var utcObj = Activator.CreateInstance(targetType);
            var objType = obj.GetType();
            // find our DateTime props
            foreach(var prop in objType.GetProperties())
            {
                var src = prop.GetValue(obj);
                if (prop.PropertyType == typeof(DateTime))
                {
                    // create the string
                    var dateUtc = (DateTime)src;
                    var utcString = dateUtc.ToString(
                        "yyyy-MM-ddThh:mm:ss.000Z", 
                        System.Globalization.CultureInfo.InvariantCulture);
                    // store
                    targetType.GetProperty(prop.Name).SetValue(utcObj, utcString);
                } else
                {
                    // normal copy
                    targetType.GetProperty(prop.Name).SetValue(utcObj, src);
                }
            }
            return utcObj;
        }
        // unknown types return the original obj
        return obj;
    }
   // omitted the other methods in the interfaces for brevity
}

使用序列化程序

这里我们创建DataContractSerializer并为其提供实例化的DTO,并在序列化之后反转该过程以检查结果是否相同。

var surrogateSerializer =
    new DataContractSerializer(
        typeof(DTO),
        new Type[] {}, 
        Int16.MaxValue, 
        false, 
        true, 
        new DTOTypeSurrogate()); // here we provide our own implementation

var ms = new MemoryStream();
// test data
var testDto = new DTO { 
    FirstDate = new DateTime(2015, 12, 31, 4, 5, 6, DateTimeKind.Utc) };
// serialize
surrogateSerializer.WriteObject(ms, testDto);
// debug
var wireformat = Encoding.UTF8.GetString(ms.ToArray());

//reset
ms.Position = 0;
//deserialize
var dtoInstance = (DTO) surrogateSerializer.ReadObject(ms);
// verify we have the same data returned
Debug.Assert(dtoInstance.FirstDate == testDto.FirstDate);