Can I use LINQ in TextTemplate?

Question

Hi,

I am using VS 2008 to design DSL,

but found that LINQ cannot be used in TextTemplate.

 

Is it possible to use Linq in tt file?

 

Thank you very much!

Answer 1

Yes, you can - this feature was added in VS2008.

 

In the template directive proceessor you need to:

1) specify the language version as either "C#v3.5" or "VBv3.5";

2) add an assembly directive to "System.Core.dll" so that the compiler picks up the core assembly; and

3) add an "import" directive to the Linq namespace.

 

e.g.

 

<#@ template language="C#v3.5" inherits="Microsoft.VisualStudio.TextTemplating.VSHost.ModelingTextTransformation"  #>
<#@ assembly name="System.Core.dll" #>
<#@ import namespace="System.Linq" #>

 

Duncan

Answer 2

Incredible!

Thank you, Thank you! Duncan!

 

Linq will be very helpful to iterate and find the object existed in the domain model.

 

Thank you so much!

Answer 3

Yes!
+1 Thanks from me.

Answer 4

Hi, I cannot get this to work.  Any ideas?

<#@ template language="C#v3.5" debug="True" inherits="Microsoft.VisualStudio.TextTemplating.VSHost.ModelingTextTransformation" #>
<#@ assembly name="System.Core.dll" #>
<#@ import namespace="System.Linq" #>
<#@ import namespace="System.Collections.Generic" #>
<#@ assembly name="C:\Solutions\Debug\MyNameSpace.MyAssembly.Business\bin\Debug\Business.dll" #>
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using MyNameSpace.MyAssembly.Business;

namespace MyNameSpace.MyAssembly.Business
{
 public enum MatterFileNoteTypes2 : int
 {
  <#
   IEnumerable<MyNameSpace.MyAssembly.Business.MatterFileNoteType> items = 
    MyNameSpace.MyAssembly.Business.MatterFileNoteType.GetMatterFileNoteTypes();
   foreach(var item in items)
   {
    WriteLine(item.Name);
   }
  #>
 }
}

I get the error: Running transformation: System.NullReferenceException.

Thanks,
Derick

Answer 5

Try adding a System.Diagnostics.Debugger.Break(); statement to your .tt, then run the transformation again.

You should then be able to step into the debugger to debug your template code (for this to work, you need to have <#@ template debug="True" ... #>, which you already do).

Regards,
Duncan