DataTable data = new DataTable("Project"); 

data.Columns.Add("Name"); 

data.Columns.Add("Birthday"); 

data.Rows.Add(new object[] { "Wendy", "1978/03/11" }); 

data.Rows.Add(new object[] { "Philip", "2000/11/05" }); 

data.Rows.Add(new object[] { "Felix", "1999/08/04" }); 

using (var ms = new MemoryStream()) 

{ 

    // 将DataTable用Xml格式写入流  

    data.WriteXml(ms, XmlWriteMode.WriteSchema); 

    var client = new WebClient(); 

    // 定义HttpRequest的Content-Type(xml,json等)  

    client.Headers.Add("Content-Type", "text/xml"); 

    var url = "http://localhost:2609/Service1.asmx/SendXml"; 

    // Send HttpRequest  

    var resp = client.UploadData(url, "POST", ms.ToArray()); 

    var strResp = System.Text.Encoding.UTF8.GetString(resp); 

    MessageBox.Show(strResp); 

}

public void SendXml() 

{ 

    // 获得客户端RAW HttpRequest  

    var inputStream = HttpContext.Current.Request.InputStream; 

    // 定义Response返回的格式是:Json  

    var response = HttpContext.Current.Response; 

    response.ContentType = "text/json"; 

    //var strXml = "";  

    //using (var sr = new StreamReader(inputStream))  

    //    strXml = sr.ReadToEnd();  

    try 

    { 

        DataTable data = new DataTable(); 

        using (var xr = XmlReader.Create(inputStream)) 

            data.ReadXml(xr); 

        // 将读入Xml的DataTable的行数返回客户端  

        string count = "/"" + data.Rows.Count + "/""; 

        response.BinaryWrite(System.Text.Encoding.UTF8.GetBytes(count)); 

    } 

    catch (Exception ex) 

    { 

        response.BinaryWrite(System.Text.Encoding.UTF8.GetBytes(ex.Message)); 

    } 

}