T4 - TT - Using custom classes in TT files

Question

I would like to use my own class define in a CS file in my TT.

Example:

public class ClassDefinition
{
    public string NameSpace { get; set; }
    public string Name { get; set; }
    public string Protection { get; set; }

    List<ClassProperty> Properties { get; set; }
}

My TT looks like:

<#@ template debug="true" hostspecific="true" language="C#" #>
<#@ output extension=".cs" #>

<#@ assembly name="System" #>
<#@ assembly name="System.Core" #>
<#@ assembly name="System.Xml"#>

<#@ import namespace="System.Xml" #>
<#@ import namespace="System.Linq" #>
<#@ import namespace="System.Text" #>
<#@ import namespace="System.Collections.Generic" #>
<#@ import namespace="System.IO" #>

<#@ include file="$(ProjectDir)ClassDefinition.cs" #>

<#

// Read the model file
XmlDocument doc = new System.Xml.XmlDocument();
doc.Load(this.Host.ResolvePath("GeneratedXmlFile.xml"));

IList<XmlNode> nodeList = new List<XmlNode>();
foreach (XmlNode node in doc.DocumentElement)
{
    switch(node.Name)
    {
        case "Model": 
        {
            ClassDefinition classDefinition = new ClassDefinition();

But I have this error message:

Compiling transformation: The type or namespace name 'ClassDefinition' could not be found (are you missing a using directive or an assembly reference?)

I checked on internet and tried to: - use include - use assembly - use USING But nothing works.

Any ideas ?

Answer 1

If I understand you correctly, you're trying to reuse a class as part of your template generation.

That class needs to be in a tt file itself, build action is set to none, custom tool - nothing. What I have is a template manager class with the following at the top:

<#@ template language="C#" #>
<#@ assembly name="System.Core" #>
<#@ import namespace="System.Linq" #>
<#@ import namespace="System.Text" #>
<#@ import namespace="System.Collections.Generic" #>
<#@ import namespace="System.Diagnostics" #>

<#+
public class TemplateManager
{

Then in the other t4 templates I use:

<#@ include file="TemplateManager.tt"#>

and then

List<Values> values = TemplateManager.PrepareVariables(code, container, itemCollection.OfType<EntityType>())

In your case that ClassDefinition.tt file would contain:

<#@ template language="C#" #>
<#@ assembly name="System.Core" #>
<#@ import namespace="System.Linq" #>
<#@ import namespace="System.Text" #>
<#@ import namespace="System.Collections.Generic" #>
<#@ import namespace="System.Diagnostics" #>

<#+
public class ClassDefinition
{
    public string NameSpace { get; set; }
    public string Name { get; set; }
    public string Protection { get; set; }

    List<ClassProperty> Properties { get; set; }
}
#>

Then you can include

<#@ include file="ClassDefinition.tt"#>