DataSet和xml相互转换问题

2017-07-04 11:18:57 248 阅读 AI 写同款 · GEO 优化AI 选题数据监测一键分发 ›

关于SVPWM七段式五段式调制后的相电压和线电压波形——大疆DJI技术笔试 1.SVPWM七段式/五段式调制的相电压和线电压波形脉宽调制（PWM）在并网变流技术中得到了广泛的应用。与正弦脉宽调制（SPWM）的控制方法相比，SVPWM方法具有直流侧电压利用率高，电压谐波小，易于数字化实现等显著的优点，从而使SVPWM在实际的应用中越来越普遍。TMS320F28335是32位浮点的DSP控制器，具有150MHz的高速处理能力，18路PWM输出，与前几代数字信号控制器相比，性能平均提高了50%。其中具体的SVPWM理论实现的原理，请参考我的博客永磁同步电机的矢量控制策略（七）一一一SV 阅读详情

读取xml文件，并转换成DataSet，随机就将DataSet再转换成XML文档，然后读取刚刚导出的xml文件会报错：根级别上的数据无效。行 2，位置 1，我看了下转换的xml文档并没有什么问题，然后将出问题位置的 “<” 删掉再加上就没问题了！很奇怪，不知道大家有没有遇到过。。。下面是我的代码：

       /// <summary>

        /// 将xml对象内容转换为dataset

        /// </summary>

        /// <param name="xmlData"></param>

        /// <returns></returns>

        private DataSet ConvertXMLToDataSet(string xmlData)

        {

            using (StringReader stream = new StringReader(xmlData))

            {

                using (XmlTextReader reader = new XmlTextReader(stream))

                {

                    try

                    {

                        DataSet xmlDS = new DataSet();

                        xmlDS.ReadXml(reader);

                        return xmlDS;

                    }

                    catch (Exception ex)

                    {

                        throw ex;

                    }

                    finally

                    {

                        if (reader != null)

                            reader.Close();

                    }

                }

            }

        }



        /// <summary>

        /// 将DataSet转换为xml对象字符串

        /// </summary>

        /// <param name="xmlDS"></param>

        /// <returns></returns>

  

        public  string ConvertDataSetToXML(DataSet xmlDS)

        {

            using (MemoryStream stream = new MemoryStream())

            {

                //从stream装载到XmlTextReader 

                using (XmlTextWriter writer = new XmlTextWriter(stream, Encoding.Unicode))

                {



                    try

                    {                       

                        //用WriteXml方法写入文件.  

                        xmlDS.WriteXml(writer);

                        int count = (int)stream.Length;

                        byte[] arr = new byte[count];

                        stream.Seek(0, SeekOrigin.Begin);

                        stream.Read(arr, 0, count);



                        UnicodeEncoding utf = new UnicodeEncoding();

                        return utf.GetString(arr).Trim();

                    }

                    catch (System.Exception ex)

                    {

                        throw ex;

                    }

                    finally

                    {

                        if (writer != null) writer.Close();

                    }

                }

            }

        }  



        /// <summary>

        /// 将DataSet转换为xml文件

        /// </summary>

        /// <param name="xmlDS"></param>

        /// <param name="xmlFile"></param>

 

        public void ConvertDataSetToXMLFile(DataSet xmlDS,string xmlFile)  

        {

            using (MemoryStream stream = new MemoryStream())

            {

                //从stream装载到XmlTextReader 

                using (XmlTextWriter writer = new XmlTextWriter(stream, Encoding.Unicode))

                {



                    try

                    {                        

                        //用WriteXml方法写入文件.  

                        xmlDS.WriteXml(writer);

                        int count = (int)stream.Length;

                        byte[] arr = new byte[count];

                        stream.Seek(0, SeekOrigin.Begin);

                        stream.Read(arr, 0, count);



                        //返回Unicode编码的文本  

                        UnicodeEncoding utf = new UnicodeEncoding();

                        StreamWriter sw = new StreamWriter(xmlFile);

                        sw.WriteLine("<?xml version=\"1.0\" encoding=\"utf-8\"?>");

                        sw.WriteLine(utf.GetString(arr).Trim());

                        sw.Close();



                    }

                    catch (System.Exception ex)

                    {

                        throw ex;

                    }

                    finally

                    {

                        if (writer != null) writer.Close();

                    }

                }

            }

        }