In T4 code generation, how can I grab a type from a referenced assembly?

Question

Since T4 runs outside of the context of a project, I don't have access to the current assembly or other assemblies. How can I register access to a referenced assembly, then grab a type from it?

Answer 1

I am guessing you want to access an assembly your building in your project. What I've done in the sample code below is adding a project to my solution called TestLib which I build to the folder .\T4Libs in the solution directory. TestLib has a class called MyHelper which holds a magic number.

FYI VS2010 SP1 added the great feature in that it no longer locks the imported assemblies so that's a good version to use.

<#@ assembly   name        = "$(SolutionDir)\T4Libs\TestLib.dll"  #>
<#@ import     namespace   = "TestLib"                            #>

<#
   var myHelper = new MyHelper ();
#>

// <#=myHelper.MagicNumber#>

Answer 2

Are you looking for the Assembly directive and/or are you looking for something in the System.Reflection.Assembly class (like LoadFile)?