Transform web.config on build with custom targets

WebConfig-Live-Transformations.xml

<!-- More read here: https://msdn.microsoft.com/en-us/library/ms366724.aspx -->

  <!-- First, we extend the "BuildDependsOn" property with our custom target for applying the transform.
  This is a cleaner/safer alternative to overloading the "AfterBuild" target: -->
  <PropertyGroup>
    <BuildDependsOn>
          $(BuildDependsOn);
          _VisualStudioApplyTransform;
    </BuildDependsOn>
  </PropertyGroup>
  <!-- Now, down to business: this is our target for applying the config transform.
  I've included some conditions, to help avoid the build from blowing up when a transform
  doesn't exist for the current configuration: -->

  <Target Name="_VisualStudioApplyTransform">
    <!-- Transform the file out to a temp file, sourcing from our Web.config file: -->
    <TransformXml 
      Source="Web.config" 
      Transform="Web.$(Configuration).config" 
      Destination="Web.config.temp" 
      Condition="Exists('Web.$(Configuration).config')" />
    <!-- Copy the temp file, back over the top of Web.config, the file handle opened by TransformXml is closed now: -->
    <Copy 
      SourceFiles="Web.config.temp"
      DestinationFiles="Web.config"
      Condition="Exists('Web.config.temp')" />
    <!-- Cleanup after ourselves: -->
    <Delete 
      Files="Web.config.temp"
      Condition="Exists('Web.config.temp')" />
  </Target>