T4 Assembly Directive

In a Visual Studio design-time text template, the assembly directive loads an assembly so that your template code can use its types. The effect is similar to adding an assembly reference in a Visual Studio project.

For a general overview of writing text templates, see Writing a T4 Text Template.

Using the Assembly Directive

The syntax of the directive is as follows:

<#@ assembly name="[assembly strong name|assembly file name]" #>

The assembly name should be one of the following:

• The strong name of an assembly in the GAC, such as System.Xml.dll. You can also use the long form, such as name="System.Xml, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089". For more information, see AssemblyName.

• The absolute path of the assembly

You can use the $(variableName) syntax to reference Visual Studio or MSBuild variables such as $(SolutionDir), and %VariableName% to reference environment variables. For example:

<#@ assembly name="$(SolutionDir)\MyProject\bin\Debug\SomeLibrary.Dll" #>

The assembly directive has no effect in a preprocessed text template. Instead, include the necessary references in the References section of your Visual Studio project. For more information, see Run-Time Text Generation by using Preprocessed T4 Text Templates.

Standard Assemblies

The following assemblies are loaded automatically, so that you do not need to write assembly directives for them:

• Microsoft.VisualStudio.TextTemplating.1*.dll

• System.dll

• WindowsBase.dll

If you use a custom directive, the directive processor might load additional assemblies. For example, if you write templates for a domain-specific language (DSL), you do not need to write assembly directives for the following assemblies:

• Microsoft.VisualStudio.Modeling.Sdk.1*.dll

• Microsoft.VisualStudio.Modeling.Sdk.Diagrams.1*.dsl

• Microsoft.VisualStudio.TextTemplating.Modeling.1*.dll

• The assembly containing your DSL.

See Also

Concepts

T4 Include Directive

Change History