C# XPath教程

　　XPATH在查找XML文挡里的元素灵活而且强大。

　　今天是我第一次用XPATH，其实我几乎都不会XPATH的写法。百度后在网上找到这个网址，里面有祥细的讲解

　　XPATH教程地址：http://www.zvon.org/xxl/XPathTutorial/Output_chi/

备忘一下，C#代码：

读取

            XmlDocument xmlDoc = new XmlDocument();
            string configStr = Application.ExecutablePath.Remove(Application.ExecutablePath.LastIndexOf('\\')) + "\\app.config";
            xmlDoc.Load(configStr);

            XmlElement elmConnectionStr = (XmlElement)xmlDoc.SelectSingleNode(@"//add[@key='ConnectionStr']");
            txtConnectionStr.Text = elmConnectionStr.GetAttribute("value");

            XmlElement elmDataType = (XmlElement)xmlDoc.SelectSingleNode(@"//add[@key='DataType']");
            cbbDataType.SelectedItem = elmDataType.GetAttribute("value");

            XmlElement elmNamespace = (XmlElement)xmlDoc.SelectSingleNode(@"//add[@key='Namespace']");
            txtNamespace.Text = elmNamespace.GetAttribute("value");

            XmlElement elmPrefix = (XmlElement)xmlDoc.SelectSingleNode(@"//add[@key='Prefix']");
            txtPrefix.Text = elmPrefix.GetAttribute("value");

            XmlElement elmOutputPath = (XmlElement)xmlDoc.SelectSingleNode(@"//add[@key='OutputPath']");
            txtOutpurtStr.Text = elmOutputPath.GetAttribute("value");

修改

            XmlDocument xmlDoc = new XmlDocument();
            string configStr = Application.ExecutablePath.Remove(Application.ExecutablePath.LastIndexOf('\\')) + "\\app.config";
            xmlDoc.Load(configStr);

            XmlElement elmOutputPath = (XmlElement)xmlDoc.SelectSingleNode(@"//add[@key='OutputPath']");
            elmOutputPath.SetAttribute("value", "123");
            xmlDoc.Save(configStr);