C:\Program Files (x86)\Common Files\microsoft shared\TextTemplating\11.0

Generating
Files with the TextTransform Utility

\Program Files\Common Files\Microsoft
Shared\TextTemplating\11.0

C:\Program Files (x86)\Common Files\microsoft
shared\TextTemplating\11.0

T4
(Text Template Transformation Toolkit) Code Generation - Best Kept Visual
Studio Secret - Scott Hanselman

T4 (Text Template Transformation Toolkit) Code Generation
- Best Kept Visual Studio Secret

十月 14, ‘08 Comments
[30] Posted in ASP.NET | Programming | Tools

Sponsored By

Rob
beat me to it. Blogging about T4
(the Text
Template Transformation Toolkit) had been on my list
literally for a year. He and I were singing its praises last night.
Hopefully I can add something small to the conversation.

What‘s the story? Well, T4 is a code generator built right
into Visual Studio. To be clear, you HAVE THIS NOW on your system…go
play. Now‘s the time to introduce code generation to your
company. If you‘re doing something twice or more, manually, in your
company, generate it.

However, it‘s not deep-deep built in, because there‘s no item
templates in File | New Item and there‘s no intellisense or syntax
highlighting.

You don‘t need this, but if you want really get the most out of T4,
first, head over to Clarius Consulting and get their "T4
Editor Community Edition." That‘ll get you some basic coloring. They
have a pay version that gets you more if you want.

Now, go into Visual Studio and make a Console App (or any app) and
add a Text File, but name it something with a .tt
extension. You‘ll get a warning since it‘s a generator, that
someone could generate evil. Click OK if you are cool with potential
evil. ;)

Now, look in Solution Explorer at the .tt
file. If you‘re using C#, you‘ll have a sub .cs file, or if you‘re using
VB, a sub .vb file. That‘s the file that will hold the result of the
generation. This is the same visual metaphor used to the express the
template/generated file relationship with .designer files you‘ve seen
elsewhere in Visual Studio.

If you look in the Properties for the .tt file, you‘ll see it‘s using
a CustomTool listed as the "TextTemplatingFileGenerator." This custom
tool extensibility point is how things like XSD and WSDL code generators
hook in to generate their artifacts.

T4 can generate any kind of text file, not just code. Whatever you
like. You can use it in your projects, as above, or you can call
T4 from the command-line.

Aside from Kzu and the folks at Clarius, Rob
notes that Oleg
Sych has a great
collection of T4 resources. He‘s got some great Tutorials:

• Creating
  your first code generator


• Troubleshooting
  code generation errors


• Debugging
  code generation files


• Creating
  reusable code generation templates


• Creating
  complex code generators


• Reusing
  code generators on multiple projects

Here‘s some
of the links from Oleg‘s blog.

• How
  to create a simple T4 template


• How
  to use T4 to generate .config files


• How
  to use T4 to generate Decorator classes


• How
  to use T4 to generate CRUD stored procedures


• How
  to use T4 to generate strongly-typed navigation class in
  ASP.NET (by Kirill Chilingarashvili)


• How
  to use T4 to generate strongly-typed AzMan wrapper


• How
  to generate multiple outputs from single T4 template


• T4
  template for generating ADO.NET Entity Framework Stored
  Procedures  (by David DeWinter)


• T4
  script for generating ADO.NET Entity Framework Views (by
  ADO.NET team)


• T4
  template for generating LINQ to SQL Data Context (by
  Damien Guard)


• T4
  template for generating WiX source files (by New Age
  Solutions)


• T4
  template for generating SQL view from C# enumeration


• MSBuild
  task for transforming T4 templates (by Elton Stoneman)
  


• T4
  template for generating state machines in C# (by Andrew
  Matthews)

Oleg also has a CodePlex project called T4
Toolbox that is a library of T4 templates that get added to File |
New Item.

Also, check out Damien
Guard‘s T4 templates that are a wholesale replacement of code that LINQ
to SQL generates. Here‘s an example, where I use Damien‘s T4
templates against the sample Chinook
Database.

Notice that I‘ve named the .tt file the same as the .dbml, so
Damian‘s code can find it. I also continue to let original LINQ to SQL
generate it‘s .designer.cs file, but make that file‘s Build Action
"None" so it‘s not ever compiled. That effectively puts Damian‘s code in
charge.

Here‘s a screenshot showing a bit of Damian‘s T4 template using the
syntax highlighting from the Clairus T4 Visual Studio free download. If
I‘d pay them, I‘d get intellisense and syntax highlighting inside
the code blocks also. It looks like a lot like ASP.NET Web Forms,
or Velocity, or any templating language really. The code blocks are
where your logic is and outside the codeblocks is the template for
whatever you want to generate. Notice how Damien gets input and sets
output. You have full control, you can read files off the file system,
from with your project, etc. He sets the output extension also. I like
to use .g.cs or .g.vb, myself. In this example his generated file is
Chinook.generated.cs.

I particularly like Damien‘s example because he‘s swapping out parts
of LINQ to SQL that he didn‘t like (the generated code) while keeping
the part he did (the general mode, the designer, the dbml file.) If you
don‘t like something, fix it.

Plus, it all works in Visual Studio without installing
anything.

If you‘re doing Code Gen, or thinking about it, check out T4
as it‘s a great place to start. Also, search my blog for "Code
Generation" as I was livign and breathing it with CodeSmith
for the many years I worked at Corillian.
Have fun!

C:\Program Files (x86)\Common Files\microsoft
shared\TextTemplating\11.0