WCF按照basicHttpBinding方式发布，.net按照Web Service方式调用，自动生成的Proxy中枚举类型和Nullable类型的参数，在Proxy里面发现一些不一样的东西，都额外生成一个配对的XXSpecified的字段和属性。你必须将该值设为true,否则,WCF序列化的时候回忽略相应的枚举类型或Nullable类型，全部使用的默认值，你所赋的值都被忽略了，只有你将XXSpecified设置为true就可以了。

[TestMethod]
        public void TestASMXSendHtmlMail()
        {
            localhost.TencentEmail mail = new localhost.TencentEmail();
            mail.EmailType = localhost.TencentMailType.SEND_TO_MEETING;
            mail.EmailTypeSpecified = true;
            mail.To = "toby";
            mail.From = "geffzhang";
            mail.CC = "mouse";
            mail.Bcc = "geffzhang";
            mail.Title = "this's a test mail ";
            mail.Content = "<H1>this's a test meeting mail. </H1>";
            mail.BodyFormat = localhost.TencentMailFormat.Html;
            mail.BodyFormatSpecified = true;
            mail.Priority = localhost.MessagePriority.Hight;
            mail.PrioritySpecified = true;
            mail.Organizer = "geffzhang";
            mail.Location = "飞亚达1003";
            mail.StartTime = DateTime.Now;
            mail.StartTimeSpecified = true;
            mail.EndTime = DateTime.Now.AddDays(1);
            mail.EndTimeSpecified = true;
            localhost.MessageService messageService = new localhost.MessageService();
            messageService.Application_Context = new localhost.ApplicationContext() { AppKey = "93ed11c73f7c4ae7a6335ffa9809e4f9" };
            bool sendResult;
            bool sendResultSpec;
            messageService.SendMail(mail, out sendResult, out sendResultSpec);
            Assert.IsTrue(sendResult);
        }

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