xml读取

项目开发中，我习惯将sql语句单独放到一个xml文档中，这样需要修改sql语句时候，就不用更新代码了。

1，展示xml文档结构：

<?xml version="1.0" encoding="utf-8" ?>
<root>
  <sql id="GetUserInfo" description="查询用户信息">
    <![CDATA[SELECT a.Id,a.userName,a.phone FROM  u_tab_user a ;]]>
  </sql>
</root>

PS：多个SQL 只需要配置多个<sql></sql> 节点即可

2，读取指定Id的SQL语句：

public class SqlMap
    {
        private const string key = "id";

        public static string GetSql(string fileName, string sqlKey)
        {
            string result = string.Empty;
            IEnumerable<XElement> element = LoadXml(fileName);
            var ele = element.Single(o => o.Attribute(XName.Get(key)).Value == sqlKey);
            if (ele != null)
            {
                result = ele.Value;
            }
            return result;
        }

        private static IEnumerable<XElement> LoadXml(string fileName)
        {
            string dirPath = AppDomain.CurrentDomain.BaseDirectory;
            string fileDir = string.Format("SqlFile/{0}.xml", fileName);
            string filePath = Path.Combine(dirPath, fileDir);
            if (!File.Exists(filePath))
            {
                fileDir = string.Format("bin/SqlFile/{0}.xml", fileName);
                filePath = Path.Combine(dirPath, fileDir);
            }
            XElement element = XElement.Load(filePath);
            return element.Descendants();
        }
}

PS： fileName 是xml文件名称例如用户模块的SQL与角色模块的SQL分开，那就建两个xml,  User.xml 和 Role.xml

另外还有些经常会变动的配置，我也习惯用xml进行配置，配置文件如下：

<?xml version="1.0" encoding="utf-8" ?>
<root>
  <user description="用户设置">
    <item key="userKey" a="10" b="0.22" c="0.67" description="说明性文字" ></item>
  </user>
  <elements description="说明性文字">
    <item key="key1" a= "1" b = "0.63" c = "0.114" type="text" fontSize="12" description="说明性文字"></item>
      <item key="key2" a= "1" b = "0.7" c = "0.5" type="text" fontSize="12" description="说明性文字"></item>
  </elements>
</root>

读取方式：

public static List<ElementObj> GetElements(string elementKey, string fid)
        {
            List<ElementObj> elements = new List<ElementObj>();
            if (string.IsNullOrEmpty(elementKey)) { return elements; }

            XmlNodeList contractItems = LoadXml(elementKey, fid, "elements");
            ElementObj model = null;
            foreach (var e in contractItems)
            {
                XmlElement item = e as XmlElement;
                if (item != null && item.NodeType == XmlNodeType.Element)
                {
                    string a= ((XmlElement)item).GetAttribute("a");   //获取a属性值  
                    string b = ((XmlElement)item).GetAttribute("b");   //获取b属性值  
                    string c = ((XmlElement)item).GetAttribute("c");   //获取c属性值  
                    string type = ((XmlElement)item).GetAttribute("type");   //获取type属性值  
                    string fontSize = ((XmlElement)item).GetAttribute("fontSize");   //获取fontSize属性值  
                    string key = ((XmlElement)item).GetAttribute("key");   //获取key属性值  
                }
            }
            return elements;
        }

        private static XmlNodeList LoadXml(string elementKey, string fid, string nodeKey)
        {
            string tempFileSavePath = AppDomain.CurrentDomain.BaseDirectory + "elements\" + elementKey + "\";
            if (!Directory.Exists(tempFileSavePath))
            {
                Directory.CreateDirectory(tempFileSavePath);
            }

            string xmlPath = Path.Combine(tempFileSavePath, fid + ".xml");//string path = string.Format("elements/{0}.xml", elementKey);
            //string xmlPath = AppDomain.CurrentDomain.BaseDirectory + path;
            XmlDocument doc = new XmlDocument();
            doc.Load(xmlPath);    //加载Xml文件  
            XmlElement rootElem = doc.DocumentElement;   //获取根节点  
            XmlNodeList elementNodes = rootElem.GetElementsByTagName(nodeKey); //获取预警类型子节点集合  
            XmlElement element = elementNodes[0] as XmlElement;
            XmlNodeList nodeItems = element.ChildNodes;
            return nodeItems;
        }