将数据集转换为XML

Question

我被这个问题困扰了几个小时，似乎无法解决，所以我在这里问一下：)

好的，我有这个函数：

private void XmlDump()
{
    XDocument doc = new XDocument(new XDeclaration("1.0", "utf-8", "yes"));
    XElement rootElement = new XElement("dump");
    rootElement.Add(TableToX("Support"));

    string connectionString = ConfigurationManager.ConnectionStrings["MyDb"].ConnectionString;
    SqlConnection con = new SqlConnection(connectionString);
    string sql = "select * from support";
    SqlDataAdapter da = new SqlDataAdapter(sql, con);

    DataSet ds = new DataSet("Test");
    da.Fill(ds, "support");

    // Convert dataset to XML here

    var docresult = // Converted XML

    Response.Write(docResult);
    Response.ContentType = "text/xml; charset=utf-8";
    Response.AddHeader("Content-Disposition", "attachment; filename=test.xml");
    Response.End();
}

我尝试了各种不同的方法，但是一直出现错误，所以我把如何将DataSet转换为XML的部分留空了。

还有一件事，这个查询包含带特殊字符的列。

- NomenNescio

Answer 1

你可以使用ds.WriteXml，但这将要求你有一个流Stream来放置输出。如果你想将输出放在一个字符串中，请尝试使用以下扩展方法：

public static class Extensions
{
    public static string ToXml(this DataSet ds)
    {
        using (var memoryStream = new MemoryStream())
        {
            using (TextWriter streamWriter = new StreamWriter(memoryStream))
            {
                var xmlSerializer = new XmlSerializer(typeof(DataSet));
                xmlSerializer.Serialize(streamWriter, ds);
                return Encoding.UTF8.GetString(memoryStream.ToArray());
            }
        }
    }
}

用法：

var xmlString = ds.ToXml();
// OR
Response.Write(ds.ToXml());

- Abdul Munim

---

是的，这个可以工作，但特殊字符会显示为问号，有没有解决方法？ - NomenNescio

那可能是由于ASCII编码的缘故。尝试使用Encoding.UTF8。正在更新代码。 - Abdul Munim

ToArray() 你是不是想说 ToString()？ - Jay Croghan

Answer 2

只需使用 Dataset.getXml():

doc.LoadXml(ds.GetXml());

- Venkat

Answer 3

请按照以下的代码示例进行编写：

DataTable dt = new DataTable("MyData");
dt.WriteXml(@Application.StartupPath + "\\DataBaseValues.xml");

或者，您也可以像Oded所说的那样，直接将dataSet转换为：

private void WriteXmlToFile(DataSet thisDataSet)
{
   if (thisDataSet == null) 
   {
      return;
   }

   // Create a file name to write to.
   string filename = "myXmlDoc.xml";

   // Create the FileStream to write with.
   System.IO.FileStream myFileStream = new System.IO.FileStream(filename, System.IO.FileMode.Create);

   // Create an XmlTextWriter with the fileStream.
   System.Xml.XmlTextWriter myXmlWriter = 
   new System.Xml.XmlTextWriter(myFileStream, System.Text.Encoding.Unicode);

   // Write to the file with the WriteXml method.
   thisDataSet.WriteXml(myXmlWriter);   
   myXmlWriter.Close();
}

- Sai Kalyan Kumar Akshinthala

Answer 4

使用 DataSet.WriteXml 方法，可以将数据集输出为 XML 格式。

- Oded

Answer 5

如果ds是您的数据集，您可以使用以下代码：

if ds is your dataset..

ds.getXml();

这有助于获取XML。

- venkk

---

上面的回答很相似 ;)。 - shA.t

Answer 6

我们也可以使用这个

  Private Function DsToXML(DataSet ds) as System.Xml.XmlDataDocument
Dim xmlDoc As System.Xml.XmlDataDocument 
    Dim xmlDec As System.Xml.XmlDeclaration
    Dim xmlWriter As System.Xml.XmlWriter
    xmlWriter = New XmlTextWriter(context.Response.OutputStream,System.Text.Encoding.UTF8)
xmlDoc = New System.Xml.XmlDataDocument(ds)
    xmlDoc.DataSet.EnforceConstraints = False
    xmlDec = xmlDoc.CreateXmlDeclaration("1.0", "UTF-8", Nothing)
    xmlDoc.PrependChild(xmlDec)
    xmlDoc.WriteTo(xmlWriter)
    Retuen xmlDoc
  End Eunction

- Pinaki Mukherjee

Answer 7

试一下这个。对我有用。

static XmlDocument xdoc = new XmlDocument(); //static; since i had to access this file someother place too
protected void CreateXmlFile(DataSet ds) 
    {
      //ds contains sales details in this code; i.e list of products along with quantity and unit
      //You may change attribute acc to your needs ; i.e employee details in the below code

        string salemastid = lbl_salemastid.Text;
        int i = 0, j=0;
        String str = "salemastid:" + salemastid;
        DataTable dt = ds.Tables[0];
        string xml = "<Orders>" ;
         while (j < dt.Rows.Count)
         {
             int slno = j + 1;
             string sl = slno.ToString();
             xml += "<SlNo>" + sl +"</SlNo>" +
                       "<PdtName>" + dt.Rows[j][0].ToString() + "</PdtName>" +
                       "<Unit>" + dt.Rows[j][1].ToString() + "</Unit>" +
                       "<Qty>" + dt.Rows[j][2].ToString() + "</Qty>";
             j++;
         }
         xml += "</Orders>";

         xdoc.LoadXml(xml);
         //Here the xml is prepared and loaded in xml DOM.

         xdoc.Save(Server.MapPath("Newsales.xml"));
         //You may also use some other names instead of 'Newsales.xml'

         //to get a downloadable file use the below code
         System.IO.MemoryStream stream = new System.IO.MemoryStream();
                XmlTextWriter xwriter = new XmlTextWriter(stream, System.Text.Encoding.UTF8);

                xdoc.WriteTo(xwriter);
                xwriter.Flush();
                Response.Clear();
                Encoding.UTF8.GetString(stream.ToArray());
                byte[] byteArray = stream.ToArray();
                Response.AppendHeader("Content-Disposition", "filename=OrderRequest.xml");
                Response.AppendHeader("Content-Length", byteArray.Length.ToString());
                Response.ContentType = "application/octet-stream";
                Response.BinaryWrite(byteArray);
                xwriter.Close();
                stream.Close();

        } 

- S.Mohamed