从C＃中的外部dll访问web.config文件

Question

I am doing a product licensing application using MVC and Webservices. Here if a product(win/web application) needs to perform license validation, then it will call the web service I have implemented in my licensing application. And it works fine. If a product want to register with this licensing application, Some code is needed to be deployed in every client product, such as code to invoke the web service, do encryption and send details to renewal page if license expired. To include these changes to every client product, I am planning to create a dll that implements these many logic and deploy to each product. Here I want to access web.config/app.config of every client application from my dll and add some keys within in tag. Is thing possible to access another application web.config file from an external dll that has been deployed to that application?

Answer 1

As discussed, below is an example of how to load a web.config and access the app settings section.

For this local example, I've moved a web.config to C:\\Web.config and are using Linq XML.

 using System.Xml.Linq;

 XDocument xdoc = XDocument.Load("C:\\web.config"); //Path to your config here!

 XElement appSettingsNode = xdoc.Elements().First()
      .Elements().FirstOrDefault(f=> f.Name == "appSettings");

 foreach (XNode node in appSettingsNode.Nodes())
 {
      var currentSetting = node.ToString(); //Here check the contents for setting you need
 }

Hope that helps