Read web.config from library consumed by the webapplicaion deployed using IIS

Question

I have a web application deployed on IIS. This web application is consuming a library which wants to access the Web.config.

Example : Foo.dll is the web application deployed on IIS Foo.Utility.dll is consumed by Foo.dll

There is a piece of code in Foo.Utility namepsace which wants to access the web.config from Foo application and read the config values

Configuration config = WebConfigurationManager.OpenWebConfiguration(null);
string cacheDir = config.AppSettings.Settings["abc"].Value;

Currently config.FilePath = C:\Windows\Microsoft.NET\Framework64\v4.0.30319\Config\web.config

Changed my code to :

Configuration config = WebConfigurationManager.OpenWebConfiguration(Assembly.GetCallingAssembly().Location);
string cacheDir = config.AppSettings.Settings["abc"].Value;

Now my Assembly.GetCallingAssembly().Location is : C:\Windows\Microsoft.NET\Framework64\v4.0.30319\Temporary ASP.NET Files\root\62f5c902\849205ff\assembly\dl3\c28d4647\10e128d3_7449d001\foo.dll

Can someone help me to understand how to read the web.config from the place where my application is deployed using IIS?

For more information or if the question is not clear then comment below. Will update it

Answer 1

You have to use ConfigurationManager from System.Configuration. First, you'll have to add a reference to System.Configuration.dll assembly, and then use it like this:

using System.Configuration;
...
string valueOfAbc = ConfigurationManager.AppSettings["abc"];

ConfigurationManager will read the config file from the application's host. In your case, the web.config file.

Reference:

1. ConfigurationManager Class
2. Application Configuration Files