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：

字符串替换
sed
-i ‘s/${param1}/${param2}' ${param3}

目标:
textbox
10


替换为:
textbox
10


文件路径:
file
50

false