msbuild get elapsed time

elapsed-time.proj

<?xml version="1.0" encoding="utf-8"?>
<Project ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
  
  <!--
  This shows how you can calculate the elapsed time in MSBuild
  -->
  
  <Target Name="BeforeBuild">
    <PropertyGroup>
      <startTime>$([System.DateTime]::Now)</startTime>
    </PropertyGroup>
  </Target>
  
  <Target Name="AfterBuild">
    
    <PropertyGroup>
      <elapsed>$([System.DateTime]::Now.Subtract($(startTime)))</elapsed>
    </PropertyGroup>
    
    <Message Text="elapsed: $(elapsed)" Importance="high"/>
    
  </Target>
  
</Project>