c# 读xml文件

XmlDocument xmlDoc = new XmlDocument();
            xmlDoc.Load("cmdCfg.xml");
            XmlNodeList nodeList = xmlDoc.SelectSingleNode("config").ChildNodes;
            if (nodeList != null)
            {
                foreach (XmlNode cmdNode in nodeList)
                {
                    XmlElement cmdElement = (XmlElement)cmdNode;
                    string id = cmdElement.GetAttribute("id");
                    XmlNodeList nls = cmdElement.ChildNodes;
                    string showName = cmdNode.SelectSingleNode("show_name").InnerText;
                    string path = cmdNode.SelectSingleNode("path").InnerText;
                    string paramStr = cmdNode.SelectSingleNode("param_str").InnerText;

                    XmlNode paramDetailNode = cmdNode.SelectSingleNode("param_detail[@name='param1']");
                    string paramDeatilShowName = paramDetailNode.SelectSingleNode("show_name").InnerText;
                }
            }

xml文件：

<?xml version="1.0" encoding="utf-8" ?>
<config>
  <cmd id="replace">
    <show_name>字符串替换</show_name>
    <path>sed</path>
    <param_str>-i ‘s/${param1}/${param2}' ${param3}</param_str>
    <param_detail name="param1">
      <show_name>目标:</show_name>
      <type>textbox</type>
      <length>10</length>
    </param_detail>
    <param_detail name="param2">
      <show_name>替换为:</show_name>
      <type>textbox</type>
      <length>10</length>
    </param_detail>
    <param_detail name="param3">
      <show_name>文件路径:</show_name>
      <type>file</type>
      <length>50</length>
    </param_detail>
    <screen_out_redirect_to_file>false</screen_out_redirect_to_file>
  </cmd>
</config>