C#读取XML文档

 下面是一个读取XML文档的比较通用的方法,可以很方便地读取XML文档格式.XML文档如下:

<? xml version="1.0" encoding="utf-8"  ?>
< RolesRoot  ID ="0"   RoleName ="应用权限配置"  RoleValue =""  RoleUrl =""  RoleMark ="" >
   < Roles  ID ="CLGL"  RoleName ="车辆管理"  RoleValue =""  RoleUrl =""  RoleMark ="" >
     < Role  ID ="CLGL_CLXX"  RoleName ="车辆基本信息"  RoleValue =""  RoleUrl ="车辆管理/车辆基本信息"  RoleMark ="" >
       < RoleChild  ID =""  RoleName ="编辑"  RoleValue =""  RoleUrl =""  RoleMark ="clbjqx" ></ RoleChild >
       < RoleChild  ID =""  RoleName ="修改"  RoleValue =""  RoleUrl =""  RoleMark ="clxgqx" ></ RoleChild >
       < RoleChild  ID =""  RoleName ="删除"  RoleValue =""  RoleUrl =""  RoleMark ="clscqx" ></ RoleChild >
     </ Role >
     < Role  ID ="CLGL_SJXX"  RoleName ="司机基本信息"  RoleValue =""  RoleUrl ="车辆管理/司机基本信息"  RoleMark ="" >
       < RoleChild  ID =""  RoleName ="编辑"  RoleValue =""  RoleUrl =""  RoleMark ="sjbjqx" ></ RoleChild >
       < RoleChild  ID =""  RoleName ="修改"  RoleValue =""  RoleUrl =""  RoleMark ="sjxgqx" ></ RoleChild >
       < RoleChild  ID =""  RoleName ="删除"  RoleValue =""  RoleUrl =""  RoleMark ="sjscqx" ></ RoleChild >
     </ Role >
   </ Roles >
   < Roles  ID ="HYGL"  RoleName =""  RoleValue =""  RoleUrl =""  RoleMark ="" >
     < Role  ID =""  RoleName =""  RoleValue =""  RoleUrl =""  RoleMark ="" ></ Role >
     < Role  ID =""  RoleName =""  RoleValue =""  RoleUrl =""  RoleMark ="" ></ Role >
     < Role  ID =""  RoleName =""  RoleValue =""  RoleUrl =""  RoleMark ="" ></ Role >
   </ Roles >
</ RolesRoot >

 读取该文档的C#代码如下所示:

   /// <summary>
    /// 获取XML文档中元素的值
    /// </summary>
    /// <param name="parentNodePath">父级节点位置，如RolesRoot/Roles</param>
    /// <param name="childNodeName">子节点名称，如要在Role节点下找相关元素值</param>
    /// <param name="matchElementName">要进行匹配的元素名称,如通过ID元素值来找匹配</param>
    /// <param name="id">ID元素值</param>
    /// <param name="elementName">需要获取的元素名称</param>
    /// <returns></returns>
    public static string GetXmlElementValue(string parentNodePath, string childNodeName,string matchElementName, string id, string elementName)
    {
        string outPut = string.Empty;
        try
        {
            string xmlpath = ConfigurationManager.AppSettings["RolesConfig"];
            XmlDocument doc = new XmlDocument();
            doc.Load(xmlpath);

            XmlNodeList nodes = doc.SelectSingleNode(parentNodePath).ChildNodes;
            foreach (XmlElement node in nodes)
            {
                if (node.Name == childNodeName)
                {
                    if (node.Attributes[matchElementName].Value == id)
                    {
                        outPut = node.Attributes[elementName].Value;
                    }
                }
            }
        }
        catch (Exception ex)
        {
            Response.Write(ex.Message);
        }
        return outPut;
    }

上面介绍了读取一般格式的XML文档的方法,下面介绍读取特殊XML文件属性的方法,该XML文档定义了ID属性,如下:

<? xml version="1.0" encoding="utf-8"  ?>
<! DOCTYPE RolesRoot [
  <!ELEMENT Role ANY >
   <! ELEMENT RoleName ANY >
   <! ELEMENT RoleValue ANY >
   <! ELEMENT RoleUrl ANY >
   <! ELEMENT RoleMark ANY >
   <! ATTLIST Role RoleID ID #REQUIRED >
   <! ATTLIST RolesRoot RoleID IDREF #REQUIRED >
]>

< RolesRoot  RoleID ="0"   RoleName ="应用权限配置"  RoleValue =""  RoleUrl =""  RoleMark ="" >
   < Role  RoleID ="CLGL"  RoleName ="车辆管理"  RoleValue =""  RoleUrl =""  RoleMark ="" >
     < Role  RoleID ="CLGL_CLXX"  RoleName ="车辆基本信息"  RoleValue =""  RoleUrl ="车辆管理/车辆基本信息"  RoleMark ="" >
       < Role  RoleID ="CLGL_CLXX_BJ"  RoleName ="编辑"  RoleValue =""  RoleUrl =""  RoleMark ="clbjqx" ></ Role >
       < Role  RoleID ="CLGL_CLXX_XG"  RoleName ="修改"  RoleValue =""  RoleUrl =""  RoleMark ="clxgqx" ></ Role >
       < Role  RoleID ="CLGL_CLXX_SC"  RoleName ="删除"  RoleValue =""  RoleUrl =""  RoleMark ="clscqx" ></ Role >
     </ Role >
     < Role  RoleID ="CLGL_SJXX"  RoleName ="司机基本信息"  RoleValue =""  RoleUrl ="车辆管理/司机基本信息"  RoleMark ="" >
       < Role  RoleID =""  RoleName ="编辑"  RoleValue =""  RoleUrl =""  RoleMark ="sjbjqx" ></ Role >
       < Role  RoleID =""  RoleName ="修改"  RoleValue =""  RoleUrl =""  RoleMark ="sjxgqx" ></ Role >
       < Role  RoleID =""  RoleName ="删除"  RoleValue =""  RoleUrl =""  RoleMark ="sjscqx" ></ Role >
     </ Role >
   </ Role >
</ RolesRoot >

我们通过ID属性读取该XML文档,获取元素的值.

    /// <summary>
    /// 通过ID获取元素值
    /// </summary>
    /// <param name="id">XML文档中定义的唯一ID属性</param>
    /// <param name="elementName">对应ID元素下要查找的元素名称</param>
    /// <returns></returns>
    public static string GetXmlElementValueById(string id, string elementName)
    {
        string outPut = string.Empty;
        try
        {
            string xmlpath = ConfigurationManager.AppSettings["RolesConfig"];
            XmlDocument doc = new XmlDocument();
            doc.Load(xmlpath);

            XmlElement elem = doc.GetElementById(id);
            outPut = elem.Attributes[elementName].Value;
        }
        catch (Exception ex)
        {
            Response.Write(ex.Message);
        }
        return outPut;
    }