Introduction
 
 Here I come with an article to help my developer community. This article is  about transforming your app.config/web.config settings based on the  configuration environment selected using package Slow cheetah. I have also  created a demo project to demonstrate how this works. Hope you find it  interesting!
 
 Background
 
 This article is a  reference.
 
 Step by step process
 
 Step 1: Install the package "Slow Cheetah" into your solution.
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 Step 2: Right click on the App.config and select the option Add  Transform.
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 The Add Transform will add the available configuration environment app.config  (like for Test the config file will be added as App.Test,Config) files under the  "App.config"
 
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 Step 3: To tweak the appsetting values ,connection strings etc based on  the configuration environement. Here I am tweaking the webServiceUrl value  based on environment.
 
 This is the default value in the App.config.
 
- <add key="webServiceURL" value="https://dev.com"/>  
 
The below setting is added into the App.Test.config. So here I am replacing the  webServiceURL value to "
http://test.com" when the selected configuration  is Test.  
- <add key="webServiceURL" value="http://test.com" xdt:Transform="Replace" xdt:Locator="Match(key)"/>  
 
Woohooo!! All done, this is how you do the transform. Now select the  configuration and run F5.  
Add Configuration Environment
  Here, I am just focusing on adding the configuration for a new environment. By  following the below steps you can configure the environment.  
Step 1: Select the configuration manager from the drop down as shown  below. The configuration Manager window pops up.  
  Step 2: Select the option <New> from the drop down "Active Solution  Configuration" to add a new environment configuration.  
  Step 3: Enter the environment name for which you want to add the  configuration and click on OK. So here I am adding the Perf environment  configuration.  
   That's All you have added the configuration for the environment. Now you can  check whether the newly added environment is added in the list or not.  
  Example
  To demonstrate this I have created a console application which will transform  config using slow cheetah. I have followed the above steps and added the three  Configuration environments "Perf","Test" and "UAT". And based on the  configuration environment selected in my demo the url value gets changed.  
  Points of Interest
  You can also preview the transformation by right clicking on the particular  config file and then select the option "Preview Transform". 
 Like here I want to preview my test config.  
  So this is how the transformed config looks now.  
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