EmbeddedResource.cs

using System;
using System.IO;
using System.Reflection;

namespace DAS.Utils
{
    public static class EmbeddedResource
    {
        /// <summary>
        ///
        /// </summary>
        /// <param name="file">The path and file name of the resource to read. Path can be separated either by forward slash, backslash, or period (.). If in a folder, the folder is relative to the project.</param>
        /// <returns></returns>
        public static Stream GetStream(string file)
        {
            if (string.IsNullOrEmpty(file)) throw new ArgumentException("File path/name not supplied.", nameof(file));
            var parsedFilePath = file.Replace('\\', '.').Replace('/', '.').TrimStart('.');

            var resourceName = $"{typeof(EmbeddedResource).Assembly.FullName.Split(',')[0]}.{parsedFilePath}";

            return GetStreamInternal(resourceName);
        }

        private static Stream GetStreamInternal(string resourceName)
        {
            var assembly = typeof(EmbeddedResource).GetTypeInfo().Assembly;
            var resourceInfo = assembly.GetManifestResourceInfo(resourceName);
            if (resourceInfo == null)
                throw new FileNotFoundException(
                    "Can't find Embedded Test Resource file. Have you set 'Build Action' to 'Embedded resource' in the file's properties?",
                    resourceName);

            return assembly.GetManifestResourceStream(resourceName);
        }

        /// <summary>
        /// Use this to figure out the data folder location by convention. The convention requires:
        ///     - That the namespace matches the data file path.
        ///     - That the data folder is the same name as the supplied <paramref name="testType"/>
        ///       but with the "Tests" prefix replaced with "Data".
        ///       E.g: Folder\ThingTests.cs -> Folder\ThingData\file.ext
        /// </summary>
        /// <param name="testType"></param>
        /// <param name="fileNameWithExtension"></param>
        /// <returns></returns>
        public static string Read(Type testType, string fileNameWithExtension)
        {
            if (testType is null) throw new ArgumentNullException(nameof(testType));
            if (string.IsNullOrEmpty(fileNameWithExtension)) throw new ArgumentException("Must be supplied", nameof(fileNameWithExtension));

            const string suffix = "Tests";
            var dataFolder = testType.FullName.EndsWith(suffix, StringComparison.Ordinal)
                ? testType.FullName.Substring(0, testType.FullName.Length - suffix.Length)
                : testType.FullName;

            var resourceName = $"{testType.FullName}.{dataFolder}Data.{fileNameWithExtension}";

            using (Stream stream = GetStreamInternal(resourceName))
            using (StreamReader reader = new StreamReader(stream))
            {
                return reader.ReadToEnd();
            }
        }

        public static string Read(string file)
        {
            using (Stream stream = GetStream(file))
            using (StreamReader reader = new StreamReader(stream))
            {
                return reader.ReadToEnd();
            }
        }
    }
}