c# - How to dynamically apply changes to app.config on program start? -

My program uses some environmental data, which is referenced in the 'app.config' file:

< Pre> & lt; Configuration & gt; ... & lt; EnvUnderTest path = "settings_a.xml" /> ... & lt; Configuration & gt;

It is necessary to switch from time to time between this data, but I do not like an idea to change the 'app.config' file directly. Therefore, I thought it was better If the program starts, the 'path' parameter will change.

Can you tell me how it can be done?

I have tried the following code:

  string te = Configuration Manager. App Settings ["EnvUnderTest"]; Configuration cfg = Configuration Manager OpenXE configuration (Configuration subcl. NO);  

but te is the variable value tap , so I do not know how I can use this parameter value at runtime .

You are not using a properly configured file: try it

  & lt; Configuration & gt; ... & lt; App settings & gt; & Lt; Add key = "EnvUnderTest" value = "settings_a.xml" /> & Lt; / AppSettings & gt; ... & lt; / Configuration & gt;  

This should work with the code provided by you. Obviously, any other key you want to add is also & lt; App settings & gt; .