Question

I have a C# project property called Version defined as

<Version Condition="$(Version)==''">1.2.3.4<Version>

1.2.3.4 is the default value.

I have a Team City system property, also called Version, set up to override. So in the custom run dialog in Team City, I can specify a value for Version and that value gets used. This works fine.

If I leave the parameter blank in Team City, however, the default value is still overwritten with blank (null?). If I delete the Team City parameter, the default value is used.

Is the condition incorrect? How can I set up the Team City property to be blank, and only override if I enter some value?

Answer 1

Updated answer after OP’s comment:

From docs:

MSBuild allows you to set properties
from the command line using the
/property or /p command line switch.
Property values received from the
command line override property values
set in the project file and property
values inherited from environment
variables.

So you can just set a property $(VersionTC) in TeamCity configuration and check if that property is empty or not and set version

<Version>$(VersionTC)<Version>
<Version Condition="'$(VersionTC)'==''">1.2.3.4<Version>

( so you set Version to VersionTC first. Then see if it empty and set the default )

Have a look at this blog post explaining all this.

---

Try something like below:

<Version Condition=" '$(Version)'=='' ">1.2.3.4<Version>

Note the ' ' (single quotes) around $(Version)