Can't add custom model to template as a parameter

[Mike875]

I get the exception
The type '' of the parameter '' did not match the type passed to the template.
The types in the template and the type being passed in to the parameter definitely match.
I've added a reference to the correct assembly in the metadata and in the generator.

The custom model contains a collection of a second custom model. The child model then has a collection of another custom model. All other properties in the models are strings and integers.

Any help will be greatly appreciated.

[mhutch]

Can you provide a small repro case, or at least a snippet of the code that causes this error?

[HGSandhagen]

I have a similar problem. I set a variable with a type, defined in a custom assembly and get the same error message: "The type 'TestT4.DataItem' of the parameter 'MyVariable' did not match the type passed to the template". The same code works when I use a parameter of type "string". (See commented out part below.)

Program.cs:

using Mono.TextTemplating;
using System.Reflection;
using TestT4;

var location = Assembly.GetEntryAssembly().Location;

string templateContent = "<#@ output extension=\".cs\" #>\r\n<#@ assembly name=\"" + location + "\" #>\r\n<#@ parameter name=\"MyVariable\" type=\"TestT4.DataItem\" #>\r\nConsole.WriteLine(<#=MyVariable.Id#> + \": \" + <#=MyVariable.Name#>);\r\n";
Dictionary<string, object> properties = new Dictionary<string, object> { { "MyVariable", new DataItem() { Id = 1, Name = "Test" } } };

// This works
//string templateContent = "<#@ output extension=\".cs\" #>\r\n<#@ parameter name=\"MyVariable\" type=\"string\" #>\r\nConsole.WriteLine(<#=MyVariable#>);\r\n";
//Dictionary<string, object> properties = new() { { "MyVariable", "Test" } };

Console.WriteLine("TemplateContent");
Console.WriteLine(templateContent);


await CallGenerator(templateContent, properties);

static async Task CallGenerator(string templateContent, Dictionary<string, object> properties) {
    var generator = new TemplateGenerator();

    ParsedTemplate parsed = generator.ParseTemplate("Test1.tt", templateContent);

    TemplateSettings settings = TemplatingEngine.GetSettings(generator, parsed);
    settings.Debug = true;
    settings.Log = Console.Out;

    var session = generator.GetOrCreateSession();
    foreach (var item in properties) {
        session[item.Key] = item.Value;
    }
    
    try {
        (string generatedFilename, string generatedContent) = await generator.ProcessTemplateAsync(parsed, "Test1.tt", templateContent, "Test1.cs", settings);

        if (generator.Errors.HasErrors) {
            Console.WriteLine("Errors:");
            foreach (var item in generator.Errors) {
                Console.WriteLine(item);
            }
        }
        Console.WriteLine("");
        Console.WriteLine(generatedContent);
    }
    catch (Exception ex) {
        Console.WriteLine(ex);
    }
}

DataItem.cs:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace TestT4 {
    public class DataItem {
        public int Id { get; set; }
        public string? Name { get; set; }
    }
}

[frobert35850]

I have a similar problem, do you have a solution ?

[HGSandhagen]

Sorry, no. I solved my problem without T4 template.

[frobert35850]

Sorry, no. I solved my problem without T4 template.

Finally, I use Razor Engine to templating, it's good