通用XML操作类（微型本地xml数据库）

使用的时候，只要先建立对象模型，把模型做为参数传递进去即可，非常方便。

 

XmlUtils<User>.CreateXMLFile(new User());
XmlUtils<User>.InsertXmlItem(User);
XmlUtils<User>.UpdateXmlItem(User);
XmlUtils<User>.DeleteXMLItem(User);

List<User> users= XmlUtils<User>.GetList();
List<User> users= XmlUtils<User>.GetListByCondition(new String[] {}, new String[] {},true);
List<User> users= XmlUtils<User>.GetListByCondition(new String[] { "Name" }, new String[] { "测" },false);
List<User> users= XmlUtils<User>.GetListByCondition(new String[] { "Name", "Id" }, new String[] { "测试", "1" }, true);

    //author：俞立全
   //Email：<a href="mailto:vv_2048@163.com">vv_2048@163.com
</a>    //Date: 2010-10-24
    /// <summary>
    /// 通用的 XML 操作类 （微型本地xml数据库）
    /// </summary>
    /// <typeparam name="T"></typeparam>
    class XmlUtils<T>
    {
        /// <summary>
        /// xml 保存路径
        /// </summary>
        private static readonly String xmlPath = @"data\";
        /// <summary>
        /// 主键名
        /// </summary>
        public static readonly String primaryPropertyName = "Id";


        /// <summary>
        /// 创建xml文件
        /// </summary>
        /// <param name="t"></param>
        public static void CreateXMLFile(T t)
        {
            String className = ReflectionUtils<T>.GetClassName(t);
            XmlDocument xmldoc = new XmlDocument();

            //加入XML的声明段落
            XmlNode xmlnode = xmldoc.CreateNode(XmlNodeType.XmlDeclaration,"", "");
            xmlnode.Value = "version=\"1.0\" encoding=\"utf-8\"";
            xmldoc.AppendChild(xmlnode);

            //加入一个根元素
            XmlElement xmlelem = xmldoc.CreateElement("Root");
            //XmlText xmltext = xmldoc.CreateTextNode ( "Root Text" ) ;
            //xmlelem.AppendChild ( xmltext ) ;
            xmldoc.AppendChild(xmlelem);
            if (!Directory.Exists(xmlPath))
            {
                Directory.CreateDirectory(xmlPath);
            }
            xmldoc.Save(xmlPath + className + ".xml");
        }

        /// <summary>
        /// 判断主键是否唯一
        /// </summary>
        /// <param name="xmldoc"></param>
        /// <param name="className"></param>
        /// <param name="o"></param>
        /// <returns></returns>
        private static Boolean IsPrimaryKeyUnique(XmlDocument xmldoc,String className,Object o)
        {
            String xPathStr = "Root/" + className + "[" + primaryPropertyName + "='"+ o.ToString() +"']";
            // XPath 查询
            XmlNodeList nodeList = xmldoc.SelectNodes(xPathStr);
            if (nodeList.Count > 0)
            {
                return false;
            }
            else
            {
                return true;
            }
         
        }

        /// <summary>
        /// 插入对象
        /// </summary>
        /// <param name="t"></param>
        public static void InsertXmlItem(T t)
        {
            String className = ReflectionUtils<T>.GetClassName(t);
            XmlDocument xmldoc = new XmlDocument();
            //加载xml文件
            try
            {
                xmldoc.Load(xmlPath + className + ".xml");
            }
            catch (Exception e)
            {

                Console.WriteLine(e.Message);
            }

            //判断 主键号是否有值 或者 主键已经存在
            Object o = ReflectionUtils<T>.GetTPropertyValue(t, primaryPropertyName);
            if (o != null && IsPrimaryKeyUnique(xmldoc, className, o))
            {
                //获取根节点
                XmlNode root = xmldoc.DocumentElement;
                //创建子节点
                XmlElement itemNode = xmldoc.CreateElement(className);

                PropertyInfo[] propertyInfos = ReflectionUtils<T>.GetPropertyInfos(t);
                foreach (PropertyInfo propertyInfo in propertyInfos)
                {
                    String propertyName = propertyInfo.Name;
                    String propertyValue = propertyInfo.GetValue(t, null) == null ? "" : propertyInfo.GetValue(t, null).ToString();
                    XmlElement propertyNode = xmldoc.CreateElement(propertyName);
                    propertyNode.InnerText = propertyValue;
                    itemNode.AppendChild(propertyNode);
                }
                root.AppendChild(itemNode);
                xmldoc.Save(xmlPath + className + ".xml");
            }
            else
            {
                throw new Exception("插入数据失败，插入的主键为空或者主键已经存在。");
            }
            
            
        }

        /// <summary>
        /// 批量插入对象
        /// </summary>
        /// <param name="list"></param>
        public static void BatchInsertXmlItem(List<T> list)
        {
            String className = typeof(T).Name;
            XmlDocument xmldoc = new XmlDocument();
            //加载xml文件
            try
            {
                xmldoc.Load(xmlPath + className + ".xml");
            }
            catch (Exception e)
            {

                Console.WriteLine(e.Message);
            }
            //获取根节点
            XmlNode root = xmldoc.DocumentElement;
            
            foreach (T t in list)
            {
                //创建子节点
                XmlElement itemNode = xmldoc.CreateElement(className);
                PropertyInfo[] propertyInfos = ReflectionUtils<T>.GetPropertyInfos(t);
                foreach (PropertyInfo propertyInfo in propertyInfos)
                {
                    String propertyName = propertyInfo.Name;
                    String propertyValue = propertyInfo.GetValue(t, null) == null ? "" : propertyInfo.GetValue(t, null).ToString();
                    XmlElement propertyNode = xmldoc.CreateElement(propertyName);
                    propertyNode.InnerText = propertyValue;
                    itemNode.AppendChild(propertyNode);
                }
                root.AppendChild(itemNode);
            }
            
            xmldoc.Save(xmlPath + className + ".xml");
        }

        /// <summary>
        /// 更新对象
        /// </summary>
        /// <param name="t"></param>
        public static void UpdateXmlItem(T t)
        {
            String className = ReflectionUtils<T>.GetClassName(t);
            XmlDocument xmldoc = new XmlDocument();
            //加载xml文件
            try
            {
                xmldoc.Load(xmlPath + className + ".xml");
            }
            catch (Exception e)
            {
                Console.WriteLine(e.Message);
            }
            // 拼接 XML XPath 查询字符串 
            String xPathStr = "Root/" + className + "[" + primaryPropertyName + "='" + ReflectionUtils<T>.GetTPropertyValue(t, primaryPropertyName) + "']";
            // XPath 查询
            XmlNodeList nodes = xmldoc.SelectNodes(xPathStr);
            if (nodes.Count > 0)
            {
                foreach (XmlNode xmlNode in nodes)
                {
                    XmlElement xmlElement = (XmlElement)xmlNode;
                    // 属性遍历
                    PropertyInfo[] propertyInfos = ReflectionUtils<T>.GetPropertyInfos(t);
                    foreach (PropertyInfo propertyInfo in propertyInfos)
                    {
                        String propertyName = propertyInfo.Name;
                        String propertyValue = propertyInfo.GetValue(t, null) == null ? "" : propertyInfo.GetValue(t, null).ToString();
                        // 更新
                        xmlElement.SelectSingleNode(propertyName).InnerText = propertyValue;
                    }
                }
                // 保存
                xmldoc.Save(xmlPath + className + ".xml");
            }
        }

        /// <summary>
        /// 删除对象
        /// </summary>
        /// <param name="t"></param>
        public static void DeleteXMLItem(T t)
        {
            String className = ReflectionUtils<T>.GetClassName(t);
            XmlDocument xmldoc = new XmlDocument();
            //加载xml文件
            try
            {
                xmldoc.Load(xmlPath + className + ".xml");
            }
            catch (Exception e)
            {
                Console.WriteLine(e.Message);
            }
            // 拼接 XML XPath 查询字符串 
            String xPathStr = "Root/" + className + "[" + primaryPropertyName + "='" + ReflectionUtils<T>.GetTPropertyValue(t, primaryPropertyName) + "']";
            // XPath 查询
            XmlNodeList nodes = xmldoc.SelectNodes(xPathStr);
            if (nodes.Count > 0)
            {
                foreach (XmlNode xmlNode in nodes)
                {
                    xmlNode.ParentNode.RemoveChild(xmlNode);
                }
                xmldoc.Save(xmlPath + className + ".xml");
            }
        }

        /// <summary>
        /// 获取所有对象
        /// </summary>
        /// <returns></returns>
        public static List<T> GetList()
        {
            List<T> list = new List<T>();
            String className = typeof(T).Name;
            XmlDocument xmldoc = new XmlDocument();
            //加载xml文件
            try
            {
                xmldoc.Load(xmlPath + className + ".xml");
            }
            catch (Exception e)
            {
                Console.WriteLine(e.Message);
            }
            XmlNodeList nodeList = xmldoc.GetElementsByTagName(className);
            foreach (XmlNode xmlNode in nodeList)
            {
                T t = Activator.CreateInstance<T>();
                XmlElement xmlElement = (XmlElement)xmlNode;
                // 属性遍历
                PropertyInfo[] propertyInfos = ReflectionUtils<T>.GetPropertyInfos(t);
                foreach (PropertyInfo propertyInfo in propertyInfos)
                {
                    String propertyName = propertyInfo.Name;
                    ReflectionUtils<T>.SetTPropertyValue(t, propertyName, xmlElement.SelectSingleNode(propertyName).InnerText);
                }
                list.Add(t);
            }
            return list;
        }

        /// <summary>
        /// 多条件查询 查询数组为空，表示查询所有
        /// </summary>
        /// <param name="pName">属性名</param>
        /// <param name="value">属性值</param>
        /// <param name="isEqual">true 等值查询，false 模糊查询</param>
        /// <returns></returns>
        public static List<T> GetListByCondition(String[] pNames, String[] values, Boolean isEqual)
        {
            List<T> list = new List<T>();
            String className = typeof(T).Name;
            XmlDocument xmldoc = new XmlDocument();
            //加载xml文件
            try
            {
                xmldoc.Load(xmlPath + className + ".xml");
            }
            catch (Exception e)
            {
                Console.WriteLine(e.Message);
            }
            // 拼接 XML XPath 查询字符串
            String condition = GetXPath(pNames,values,isEqual);
            String xPathStr = "Root/" + className + condition;

            // XPath 查询
            XmlNodeList nodeList = xmldoc.SelectNodes(xPathStr);

            foreach (XmlNode xmlNode in nodeList)
            {
                T t = Activator.CreateInstance<T>();
                XmlElement xmlElement = (XmlElement)xmlNode;
                // 属性遍历
                PropertyInfo[] propertyInfos = ReflectionUtils<T>.GetPropertyInfos(t);
                foreach (PropertyInfo propertyInfo in propertyInfos)
                {
                    String propertyName = propertyInfo.Name;
                    ReflectionUtils<T>.SetTPropertyValue(t, propertyName, xmlElement.SelectSingleNode(propertyName).InnerText);
                }
                list.Add(t);
            }
            return list;
        }



        /// <summary>
        /// 拼接 XPath 查询条件参数
        /// 等值查询：String xPath = "users/user[username='huo' and password='123']";
        /// 模糊查询：String xPath = "users/user[contains(username,'huo') and contains(password,'123')]";
        /// </summary>
        /// <param name="pNames"></param>
        /// <param name="values"></param>
        /// <returns></returns>
        private static String GetXPath(String[] pNames, String[] values, Boolean isEqual)
        {
            StringBuilder sb = new StringBuilder();
            //等值查询
            if (isEqual)
            {
                //添加第一个元素
                if (pNames.Length > 0)
                {
                    sb.Append("[");
                    sb.Append(pNames[0]);
                    sb.Append("='");
                    sb.Append(values[0]);
                    sb.Append("'");
                }
                //添加后续元素
                if (pNames.Length > 1)
                {
                    for (int i = 1; i < pNames.Length; i++)
                    {
                        sb.Append(" and ");
                        sb.Append(pNames[i]);
                        sb.Append("='");
                        sb.Append(values[i]);
                        sb.Append("'");
                    }
                }
                //结尾加上 ]
                if (sb.Length > 0)
                {
                    sb.Append("]");
                }
            }
            else   //模糊查询
            {
                //添加第一个元素
                if (pNames.Length > 0)
                {
                    sb.Append("[");
                    sb.Append("contains(");
                    sb.Append(pNames[0]);
                    sb.Append(",'");
                    sb.Append(values[0]);
                    sb.Append("')");
                }
                //添加后续元素
                if (pNames.Length > 1)
                {
                    for (int i = 1; i < pNames.Length; i++)
                    {
                        sb.Append(" and ");
                        sb.Append("[");
                        sb.Append("contains(");
                        sb.Append(pNames[i]);
                        sb.Append(",'");
                        sb.Append(values[i]);
                        sb.Append("')");
                    }
                }
                //结尾加上 ]
                if (sb.Length > 0)
                {
                    sb.Append("]");
                }
            }
            return sb.ToString();
        }
    }