title: Web Deploy and Parameters.xml: How to share parameters among multiple projects
body: <p>I have a number of web apps in a suite.  I use Web Deploy to publish the deployment packages that I build with Visual Studio.  With these packages comes a SetParameters.xml file that can be used to modify values in the web.config.  Several values are done automatically, such as connection strings, but one can add a parameters.xml file to a project in order to specify values that should be parameterizable:</p>
  
  <pre><code> &lt;?xml version="1.0" encoding="utf-8" ?&gt;
       &lt;parameters&gt;
           &lt;parameter name="Sharepoint service principal name"
                      description="The principal name of the Sharepoint service."
                      defaultValue="host/108.125.111.137"&gt;
                &lt;parameterEntry kind="XmlFile"
                                scope="\\Web\.config$"
                                match="/configuration/system.serviceModel/client/endpoint/identity/servicePrincipalName/@value"/&gt;
           &lt;/parameter&gt;
      &lt;/parameters&gt;
  </code></pre>
  
  <p>My question is:  if all of my web apps have an app setting in web.config with the same key and value that I want to modify at deployment, how can I avoid duplicating the particular parameter in every parameters.xml file?  Is there a way to put this tag in a single location and have each parameters.xml reference that common location instead?</p>