Get web.config file in timer job

I was working on timer job & wanted to get data from sql server. To achive this goal, I add my database connection string in web application’s web.config file.

Now I used the following code to get web.config setting from timer job :

private string getConnectionString()

        {

            return System.Configuration.ConfigurationManager.AppSettings["MyAppSettingKey"];     

  }

But this code was not able to get the web.config file.

Why?

I started some R & D on it & found that Time Job runs under OWSTimer.exe & Web Application runs under W3WP.exe. As the context of  Both are different so we have to use WebConfigurationManager to get specific SharePoint Web Application configuration.

private string getConnectionString(string webAppName)

        {

            System.Configuration.Configuration webConfiguration = WebConfigurationManager.OpenWebConfiguration("/", webAppName);

            return webConfiguration.AppSettings.Settings["MyAppSettingKey "].Value;

        }

This code is working in Timer Job.