节点类型 Text 不支持 ReadElementContentAsString 方法

Question

我正在尝试解析 XML 并使用 XMLreader 从中获取所有信息。由于某种原因，它从标题中抛出了错误。这是xml：

<?xml version="1.0" encoding="utf-8" ?>
<queries>
  <selectparent table="Associates">"SELECT * FROM @table"</selectparent>
  <selectchild table="VehicleContract">"SELECT * FROM @table"</selectchild>
  <addchild table="VehicleContract" read="contractId, regNr, assoc_id, percentage, vehicleType, trailerNr">"INSERT into @table (contractId, regNr, assoc_id, percentage, vehicleType, trailerNr) VALUES (@id, @reg, @assort, @perc, @type, @trailer)"</addchild>
  <updatechild table="VehicleContract" read="contractId, regNr, assoc_id, percentage, vehicleType, trailerNr">"UPDATE @table SET regNr=@reg, assoc_id=@assort, percentage=@perc, vehicleType=@type, trailerNr=@trailer WHERE contractId=@id"</updatechild>
  <removechild table="VehicleContract" read="id">"DELETE from @table WHERE contractId=@id"</removechild>
</queries>

还有我的方法：

public string selectParent, selectChildren, addChildren, updateChildren, removeChildren;
public string[] addParams, updateParams, removeParams;
XmlTextReader reader = new XmlTextReader(base.Path);
reader.WhitespaceHandling = WhitespaceHandling.None;
reader.Read();
reader.Read(); 
reader.Read();
selectParent = reader.ReadElementContentAsString();
reader.Read();
selectChildren = reader.ReadElementContentAsString();
addParams = reader.GetAttribute("read").Split(',');
addChildren = reader.ReadElementContentAsString();
updateParams = reader.GetAttribute("read").Split(',');
updateChildren = reader.ReadElementContentAsString();
removeParams = reader.GetAttribute("read").Split(',');
removeChildren = reader.ReadElementContentAsString();

我在这一行得到错误： selectParent = reader.ReadElementContentAsString 有什么问题？我不断添加reader.Read()，因为我不断收到相同的错误，但在不同的节点类型上。

据我所知，table 属性应该替换查询中的@table...但是有些不对劲。有什么想法吗？

Answer 1

我会使用 xml linq

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Xml;
using System.Xml.Linq;

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            string xml =
                "<?xml version=\"1.0\" encoding=\"utf-8\" ?>" +
                "<queries>" +
                  "<selectparent table=\"Associates\">\"SELECT * FROM @table\"</selectparent>" +
                  "<selectchild table=\"VehicleContract\">\"SELECT * FROM @table\"</selectchild>" +
                  "<addchild table=\"VehicleContract\" read=\"contractId, regNr, assoc_id, percentage, vehicleType, trailerNr\">\"INSERT into @table (contractId, regNr, assoc_id, percentage, vehicleType, trailerNr) VALUES (@id, @reg, @assort, @perc, @type, @trailer)\"</addchild>" +
                  "<updatechild table=\"VehicleContract\" read=\"contractId, regNr, assoc_id, percentage, vehicleType, trailerNr\">\"UPDATE @table SET regNr=@reg, assoc_id=@assort, percentage=@perc, vehicleType=@type, trailerNr=@trailer WHERE contractId=@id\"</updatechild>" +
                  "<removechild table=\"VehicleContract\" read=\"id\">\"DELETE from @table WHERE contractId=@id\"</removechild>" +
                "</queries>";

            XDocument doc = XDocument.Parse(xml);

            var results = doc.Elements("queries").Select(x => new
            {
                selectParent = x.Elements("selectparent").Select(y => new
                {
                    table = (string)y.Attribute("table"),
                    value = y.Value
                }).FirstOrDefault(),
                selectChild = x.Elements("selectchild").Select(y => new
                {
                    table = (string)y.Attribute("table"),
                    value = y.Value
                }).FirstOrDefault(),
                addChild = x.Elements("addchild").Select(y => new
                {
                    table = (string)y.Attribute("table"),
                    read = (string)y.Attribute("read"),
                    value = y.Value
                }).FirstOrDefault(),
                updateChild = x.Elements("updatechild").Select(y => new
                {
                    table = (string)y.Attribute("table"),
                    read = (string)y.Attribute("read"),
                    value = y.Value
                }).FirstOrDefault(),
                removeChild = x.Elements("removechild").Select(y => new
                {
                    table = (string)y.Attribute("table"),
                    read = (string)y.Attribute("read"),
                    value = y.Value
                }).FirstOrDefault(),
            }).FirstOrDefault();
        }
    }
}