DD.WellWorkover.Cloud/AsbCloudInfrastructure/AssemblyExtensions.cs

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

namespace AsbCloudInfrastructure
{
    public static class AssemblyExtensions
    {
        public static async Task<Stream> GetTemplateCopyStreamAsync(this Assembly assembly, string templateName, CancellationToken cancellationToken)
        {
            var resourceName = assembly
                .GetManifestResourceNames()
                .FirstOrDefault(n => n.EndsWith(templateName))!;

            using var stream = Assembly.GetExecutingAssembly()
                .GetManifestResourceStream(resourceName)!;

            var memoryStream = new MemoryStream();
            await stream.CopyToAsync(memoryStream, cancellationToken);
            memoryStream.Position = 0;

            return memoryStream;
        }
    }
}