ASP NET MVC 3 T4 Template Properties

Here are the properties that ASP.NET MVC 3.0 provides to T4 templates when you use the Add View and Add Controller dialogs inside Visual Studio 2010.

Add Controller

Property Name	Type	Description
AddActionMethods	Boolean	Adds action methods to the generated controller class.
AreaName	System.String	The name of the Area that the controller is created for.
ContextType	System.Type	The type of the data context.
ControllerName	String	The name of the controller class that will be generated.
ControllerRootName	String	The name of the controller class excluding the Controller part at the end of the name.
EntitySetName	String	Name of the property on the data context class containing the set of entities.
ModelType	System.Type	The type of the model class specified in the Add Controller dialog.
Namespace	String	Namespace that will be used for the generated controller class.
PrimaryKeys	PrimaryKey[] (Microsoft. VisualStudio. Web.Mvc. Scaffolding. BuiltIn)	Primary keys for the model. See table at end for PrimaryKey properties.
RelatedProperties	Dictionary<String, RelatedModel (Microsoft. VisualStudio. Web. Mvc. Scaffolding. BuiltIn)>	Related properties on the model. See table at end for RelatedModel properties.

Add View

Property Name	Type	Description
AreaName	System.String	The name of the Area that the view is being created for.
ContentPlaceHolderIDs	List<string>	List of content place holder IDs in the master page.
IsContentPage	Boolean	True if the generated view will be created with a master page or a Razor layout page.
IsPartialView	Boolean	True if the generated view is a partial view (e.g. an ASP.NET user control).
MasterPageFile	String	Master page file or Razor layout to be used with view (e.g. ~/Views/Shared/Site.Master).
Namespace	String	Namespace that will be used for the generated view.
PrimaryContentPlaceHolderID	String	Primary content place holder ID to be used when creating a view using a master page.
ReferenceScriptLibraries	Boolean	True if checked in the Add View dialog.
ViewDataType	System.Type	The view model's type.
ViewDataTypeName	String	Fully qualified name for the view model's type.
ViewName	String	Name of the view.

Common Properties

Property Name	Type	Description
AssemblyPath	List<string>	List of assemblies referenced by the project and the project's output assembly. Internal use.
Errors	CompilerErrorCollection (System.CodeDom.Compiler)	Used to stored errors that occur whilst processing the T4 template. Internal use.
FileEncoding	System.Text.Encoding	The encoding of the file that will be generated.
FileExtension	String	Not set.
FrameworkVersion	System.Version	The .NET framework version.
OutputFileExtension	System.String	The extension of the file that will be generated.
TemplateFile	System.String	The full path to the T4 template file being used.

Primary Key Properties

Property Name	Type	Description
Name	String
ShortTypeName	String
Type	System.Type

Related Model Properties

Property Name	Type	Description
DisplayPropertyName	String
EntitySetName	String
ForeignKeyPropertyName	String
PrimaryKey	String
PropertyName	String
TypeName	String

T4 Import Directive - Namespace Alias

How do you specify a namespace alias when using the Import directive in a T4 template?

The Import directive in a T4 template is used to bring a namespace into scope for any code that will be run when processing the T4 template. Here is an example template that imports the System.IO namespace without using a namespace alias.

<#@ template language="C#" #> 
<#@ output extension=".txt" #> 
<#@ import namespace="System.IO" #> 
<# 
 string text = File.ReadAllText(@"d:\MyFile.txt"); 
#> 
File content: <#= text #>

The T4 template reads all the text in the d:\MyFile.txt which is then saved in the file generated by the template.

If we want to use a namespace alias we can specify it in the import directive in a similar way to how you can with C# or VB.NET. Here is the example template modified so that an alias of IO is used for the System.IO namespace.

<#@ template language="C#" #> 
<#@ output extension=".txt" #> 
<#@ import namespace="IO = System.IO" #> 
<# 
 string text = IO.File.ReadAllText(@"d:\temp\test.xsd"); 
#> 
File content: <#= text #>

Why does this Work?

T4 templates use the CodeDom to generate C# or VB.NET code which is then executed as the template is processed. When the T4 templating engine processes the Import directive it creates a CodeNamespaceImport object and passes it the Namespace attribute's value. The CodeNamespaceImport object supports generating a namespace alias when you specify a string of the form "Alias = Namespace" and pass this to its constructor.