/// <summary>
        /// 读取XML文件中的指定元素名称的指定属性值
        /// </summary>
        /// <param name="xmlPath"></param>
        /// <param name="ElmentName"></param>
        /// <param name="AttributeName"></param>
        /// <returns></returns>
        /*
        XML格式如下
       <FW Key="141101"  Mapping="6"/>
       调用方法如下：
       GeElementString(路径,FW,Key/Mapping)
        */
        public static string GetElementString(string xmlPath, string ElmentName, string 
AttributeName)
        {
            XmlTextReader xmlRd = new XmlTextReader(xmlPath);
            string strResult = "";
            try
            {
                while (xmlRd.Read())
                {
                    if (xmlRd.NodeType == XmlNodeType.Element && 
xmlRd.Name.Equals(ElmentName))
                    {
                        strResult = xmlRd.GetAttribute(AttributeName);
                    }
                }
                xmlRd.Close();
            }
            catch (Exception)
            {
            }
            finally
            {
                xmlRd.Close();
            }
            return strResult;
        }
        
        /// <summary>
        /// 写入指定XML中指定元素名称内的属性值
        /// </summary>
        /// <param name="xmlPath"></param>
        /// <param name="ElmentName"></param>
        /// <param name="AttributeName"></param>
        /// <param name="Value"></param>
        public static void WriteElementString(string xmlPath, string ElmentName, string 
AttributeName, string Value)
        {
            XmlDocument xmlDoc = new XmlDocument();
            xmlDoc.Load(xmlPath);
            XmlNodeList node = xmlDoc.GetElementsByTagName(ElmentName);
            foreach (XmlNode node1 in node)
            {
                node1.Attributes[AttributeName].Value = Value;
            }
            xmlDoc.Save(xmlPath);
        }