app.config的读写、更新问题 两篇链接

有关App.config的基础讲解：读取并修改App.config文件

XML文件更新appsettings方法：修改App.config配置文件(项目总结)

整理后的更新方法：

public static void SetValueByKey(string newKey, string newValue)
{
try
{
string filePath = new DirectoryInfo(Application.StartupPath).Parent.Parent.FullName + "\\App.Config";
//建立一个XmlDocument对象
XmlDocument webconfigDoc = new XmlDocument();
//找到节点的xml路径
string xPath = "/configuration/appSettings/add[@key='" + newKey + "']";
//加载web.config文件
webconfigDoc.Load(filePath); //读出路径放到txtfilepath文本框中
XmlNode passkey = webconfigDoc.SelectSingleNode(xPath);
passkey.Attributes["value"].InnerText = newValue;

//保存设置
webconfigDoc.Save(filePath);
}
catch (Exception ex)
{
throw ex;
}
}