如何将 DataTable 序列化为 json 或 xml

Question

我正在尝试将 DataTable 序列化为 Json 或 XML。可能吗？如何？任何教程和想法，请。

例如有一个sql表：

CREATE TABLE [dbo].[dictTable](
    [keyValue] [int] IDENTITY(1,1) NOT NULL,
    [valueValue] [int] NULL,
 CONSTRAINT [Psd2Id] PRIMARY KEY CLUSTERED 
(
    [keyValue] ASC
)WITH (PAD_INDEX  = OFF, IGNORE_DUP_KEY = OFF) ON [PRIMARY]
) ON [PRIMARY]

C#代码：

string connectionString =
          "server=localhost;database=dbd;uid=**;pwd=**";

            SqlConnection mySqlConnection = new SqlConnection(connectionString);
            string selectString =  "SELECT keyValue, valueValue FROM dicTable";

            SqlCommand mySqlCommand = mySqlConnection.CreateCommand();

            mySqlCommand.CommandText = selectString;

            SqlDataAdapter mySqlDataAdapter = new SqlDataAdapter();

            mySqlDataAdapter.SelectCommand = mySqlCommand;

            DataSet myDataSet = new DataSet();

            mySqlConnection.Open();

            string dataTableName = "dictionary";
            mySqlDataAdapter.Fill(myDataSet, dataTableName);

            DataTable myDataTable = myDataSet.Tables[dataTableName];
            //now how to serialize it?

Answer 1

对于 XML 来说很简单：

DataTable myTable = new DataTable();
myTable.WriteXml(@"c:\myfile");

Answer 2

以下是如何将其转换为 Json：

        DataTable dt = new DataTable();
        dt.Load(reader);
        string temp = JsonConvert.SerializeObject(dt);

如果您想将此 json 转换为对象列表（可能是您的 EF 表），请使用以下命令：

dbContext db = new dbContext();
List<Object> jsonList = (List<Object>)JsonConvert.DeserializeObject(temp, typeof(List<Object>));

Answer 3

让我尝试回答你的问题。当涉及到数据集或数据表的序列化时，不要持久化到文件并回读。这会导致 IO 开销，并且并非在所有情况下都可行。您需要做的是编写一个函数来序列化数据表。 （确保为 DataTable 指定名称以便序列化。请参阅下面的 C# 示例

/*使用此方法将给定对象序列化为 XML。稍后我们会将数据表传递给此 */

    private XmlElement Serialize(object obj)
    {
        XmlElement serializedXmlElement = null;  

        try
        {
            System.IO.MemoryStream memoryStream = new MemoryStream();
            System.Xml.Serialization.XmlSerializer xmlSerializer = new System.Xml.Serialization.XmlSerializer(obj.GetType());
            xmlSerializer.Serialize(memoryStream, obj);
            memoryStream.Position = 0;

            XmlDocument xmlDocument = new XmlDocument();
            xmlDocument.Load(memoryStream);
            serializedXmlElement = xmlDocument.DocumentElement;
        }
        catch (Exception e)
        {
            //logging statements. You must log exception for review
        }

        return serializedXmlElement; 
    }

实现后序列化方法，您可以序列化您的数据表，如下所示，为了简洁起见，我不会在这里编写整个示例，

        adapter.Fill(employee);
        employee.TableName = "Employees";
        XmlElement xmlElement = (XmlElement)Serialize(employee);
        Console.WriteLine(xmlElement.ToString());
        string xmlString = xmlElement.OuterXml.ToString();

        return xmlString;

如果您有更多问题，请告诉我。