Include another t4 template dynamically

Question

I'm working with t4 templates and faced with following problem. I need include another existing t4 template to my template. But I have one restriction: name of included t4 template file is generated dynamically. I used include directive for this, but it doesn't work.

<#@ include file="\Helpers\<# FileName.tt#>" #>

I get an error:

 An unexpected start or end tag was found within a block. Make sure that you did not mis-type a start or end tag, and that you do not have any nested blocks in the template.

Value of property FileName is generated dynamically

Why would you generate T4? I can not think of any scenerio where the additonal step makes sense. — Toxantron, Jun 08 '16 at 15:38
@Toxantron,I have a few t4 template files. And depends on situation I should include one of them to my template. But which one will be included is determined by config file. — Mykhalik, Jun 08 '16 at 15:42
Have you tried? `<#@ include file=string.Format(@"\Helpers\{0}.tt", FileName) #>` — Toxantron, Jun 08 '16 at 15:54
I think there is no way to use include here, because the way I see it, include is resolved at compile time. Is it a runtime template? — Toxantron, Jun 08 '16 at 16:16
In this case the rules of OO design apply. Each template is just a class and you can use the objects with interface etc. to do that. — Toxantron, Jun 08 '16 at 16:30

score 0 · Answer 1 · edited May 23 '17 at 12:06

In order to use a parameter, you need to setup msbuild property (say in the BeforeBuild target) or pass to msbuild as /p:TargetPath="[path]", and you can use them with the following:

<#@ include file="$(TargetPath)\TargetFile.tt" #>

(more information on MSBuild properties usage here)

Additionally, you can configure t4 templates to run on each build

<!-- This line could already present in file. If it is so just skip it  -->
<Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
<!-- process *.tt templates on each build  -->
<PropertyGroup>
    <TransformOnBuild>true</TransformOnBuild>
</PropertyGroup>
<Import Project="$(MSBuildExtensionsPath)\Microsoft\VisualStudio\TextTemplating\v10.0\Microsoft.TextTemplating.targets" />

... as mentioned here: Get Visual Studio to run a T4 Template on every build

Include another t4 template dynamically

1 Answers1