I want to read the app.config value, show it in a message box, change the value using an external text editor, and finally show the updated value.

I tried using the following code:

private void button2_Click(object sender, EventArgs e)
{
    Configuration config = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);
    ConfigurationManager.RefreshSection("appSettings");
    ConfigurationManager.RefreshSection(config.AppSettings.SectionInformation.Name);
    MessageBox.Show(ConfigurationManager.AppSettings["TheValue"]);
}

But it doesn't work. It shows the old value (before changing in external text editor). Any suggestions?

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<appSettings>
  <add key="TheValue" value="abc"/>
</appSettings>
</configuration>
c# .net app-config config
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