Question

I have a custom configuration file in my asp.net website, named urls.config, which contains simple key value, just for redirection purpose, now I want to read this file programmatically and also add values in this file, I am able to use XMLTextReader and XMLDocument to read value from this file, but i am unable to add values in this file.

Any help will be greatly appreciated.
Here is my structure for the configuration file:

<rewriteMaps>  
  <rewriteMap name="StaticRewrites" />  
  <add key="/superstars4012" value="/article.aspx?articleid=4012" />  
  <add key="/superstars4013" value="/article.aspx?articleid=4013" />  
  <add key="/superstars4014" value="/article.aspx?articleid=4014" />  
  <add key="/superstar" value="/article.aspx?articleid=4012" />  
</rewriteMaps>  


XmlDocument doc = new XmlDocument();
doc.Load(Server.MapPath("urls.config"));
XmlElement element = doc.CreateElement("add");
element.SetAttribute("key", txtAddVanity.Text);
element.SetAttribute("value", "/article.aspx?articleid=4012");
doc.DocumentElement.AppendChild(element);
doc.Save(Server.MapPath("urls.config"));

this works well if the file extension is .xml, but does not when i change it to .config, my requirement is .config, as redirects does not work in .xml

Answer 1

As eloquently stated in this msdn post, modifying the web.config file while the application is running is certainly possible (as it is just text, after all) but would be a very bad idea, in that modifying the config file will result in the application being restarted on the server — ending any sessions with current users, and all new visitors seeing an error page until the application is restarted. Certainly not ideal.

From the look of your code,

<add key="/superstar" value="/article.aspx?articleid=4012" />  

It appears you are doing url rewriting from a static url to a dynamic query string. There are much better ways of accomplishing this. One is the IIS module “user-friendly urls.” I have very few problems that I couldnt solve using this module.

Its logic is as follows:

1. user enters “http://www.domain.com/page-this-or-that
2. IIS has a regex rule that matches that url pattern and catches the url
3. the user is directed to http://www.domain.com/page?id=page-this-or-that
4. You recieve the querystring and store it in a string
5. You then execute a database call that retrieves and displays the database row with the title “page-this-or-that”

This would be much easier to maintain, as well as safer for your application and your users.

-Cheers!