James Thigpen

Most build servers set an environment variable BUILD_NUMBER on every build that is auto-incremented. We can do this using WiX proprocessor. (Note, the link is for WiX 2.0 Manual, I couldn’t find a reference for WiX 3.0 Preprocessor.  Maybe it’s the same? Probably not.)

I wanted to increment my WiX installers Product Version field automatically based off this number.

Here’s the top of my Product.wxs:

<?xml version="1.0" encoding="UTF-8"?>
<Wix xmlns="http://schemas.microsoft.com/wix/2006/wi">

  <!-- Set version based on build_number env. variable. -->
  <?ifdef env.BUILD_NUMBER ?>
    <?define PRODUCTVERSION="1.0.$(env.BUILD_NUMBER).0"?>
  <?else?>
    <?define PRODUCTVERSION="1.0.0.0"?>
  <?endif?>

  <Product Id="THE_GUID_YOU_GENERATED"
           Name="My Application Name"
           Language="1033"
           Version="$(var.PRODUCTVERSION)"
           Manufacturer="My Manufacturer Name"
           UpgradeCode="THE_GUID_YOU_GENERATED">

...

The ifdef part is very picky. At first I tried <?ifdef $(env.BUILD_NUMBER) ?>, which totally doesn’t work. Then I tried <?ifdef BUILD_NUMBER ?>, which also totally doesn’t work. The above is the only thing I could get to work, which goes against what this guy says. The WiX documentation for the preprocessor is pretty shoddy.

Also notice that I am incrementing the 3rd of the 4 version numbers. Why? No idea. Maybe you can tell me.

So YMMV, Caveat Emptor, and all the crap.

WiX Arcanum!