public void GetBase64StringTest()
        {
            {
                var result = StreamUtility.GetBase64String(GetStream(str));
                Assert.AreEqual(baseString, result);
            }

            #region 测试异步方法

            Console.WriteLine("=== 测试异步方法 ===");
            Task.Run(async() =>
            {
                var result = await StreamUtility.GetBase64StringAsync(GetStream(str));
                Assert.AreEqual(baseString, result);

                Console.WriteLine("=== 异步完成 ===");
            }).GetAwaiter().GetResult();

            #endregion
        }