在Silverlight开发基于http协议客户端连接器(二)

上一篇中我们能够通过自己的WebClientEx与web应用进行通讯，这样我们就能像js中使用ajax那样异步的通过xml或json等格式进行数据收发了。

不过每次都让人家new 一个WebClientEx对象，手动传URI不说，还要管理一个共享的CookieContainer就显得笨拙了。

好吧，我们提供Message基类和一个连接器的上下文类WebConnectorContext。

Message中包含一个消息号（MessageId），一个Parameters字典。另外一个CurrentParameterUrlPart属性，该属性会自动将当前的baseurl与parameters进行拼接，过滤无效参数然后返回一个完整的url。对于一个自定义消息可以从Message继承过来，设置一下有效参数即可。

WebConnecorContext对外只提供一个AddMessageToSend方法，在该方法中设置Message和回调即可。

  

下面是Message，WebConnectorContext代码还有自定义消息类LoginMessage的代码

 

public class Message 
    { 
        public static readonly string INVALID_MESSAGE_ID = "INVALID_MESSAGE_ID"; 
        protected static readonly string _messageId = "messageId"; 
        public static readonly string UrlParamSeparator = "?"; 
        public static readonly string ParamsSeparator = "&"; 
        public static readonly string EqualSeparator = "="; 
        public Message() 
        { 
            init(); 
        } 
        private void init() 
        { 
            MessageId = INVALID_MESSAGE_ID; 
            Parameters = new Dictionary<string, string>(); 
            AvaliableParameterNames = new List<string>(); 
        } 
        protected string MessageId { get; set; } 
        public Dictionary<string, string> Parameters 
        { 
            get; 
            private set; 
        } 
        protected List<string> AvaliableParameterNames; 
        public string CurrentParameterUrlPart 
        { 
            get 
            { 
                string strBuilder = UrlParamSeparator; 
                strBuilder += _messageId + EqualSeparator + MessageId; 
                foreach (var pair in Parameters) 
                { 
                    if (AvaliableParameterNames.Contains(pair.Key)) 
                    { 
                        strBuilder = strBuilder.AppendParameterToUrl(pair.Key, pair.Value); 
                    } 
                    else 
                    { 
                        System.Diagnostics.Debug.WriteLine(string.Format("没有相应消息规则{0},将忽略此参数：", pair.Key)); 
                    } 
                } 
                return strBuilder; 
            } 
        } 
    } 
    public static class StringExtension 
    { 
        public static string AppendParameterToUrl(this string s, string key, string value) 
        { 
            return s + Message.ParamsSeparator 
                     + key 
                     + Message.EqualSeparator 
                     + value; 
        } 
    }

 

 

 

public class LoginMessage : Message 
    { 
        public  readonly static string Uid = "178_sig_uid"; 
        public readonly static string Signtime = "178_sig_time"; 
        public readonly static string Appid = "178_sig_appId"; 
        public readonly static string Appversion = "178_sig_v"; 
        public readonly static string Isaddapp = "178_sig_added"; 
        public readonly static string Sessionkey = "178_sig_sessionId"; 
        public readonly static string Friendlist = "178_sig_friends"; 
        public readonly static string Signsumber = "178_sig_key"; 
        public LoginMessage() 
        { 
            init(); 
        } 
        public LoginMessage(PageSignEntity dataEntity) 
        { 
            init(); 
            base.Parameters[LoginMessage.Uid] = dataEntity.Id; 
            base.Parameters[LoginMessage.Appid] = dataEntity.Appid; 
            base.Parameters[LoginMessage.Appversion] = dataEntity.Appversion; 
            base.Parameters[LoginMessage.Signtime] = dataEntity.Signtime; 
            base.Parameters[LoginMessage.Signsumber] = dataEntity.Signsumber; 
            base.Parameters[LoginMessage.Sessionkey] = dataEntity.Sessionkey; 
            base.Parameters[LoginMessage.Isaddapp] = dataEntity.Isaddapp; 
            base.Parameters[LoginMessage.Friendlist] = dataEntity.Friendlist; 
        } 
        private void init() 
        { 
            base.MessageId = "10000"; 
            //可以用反射少些代码，或用code generater的方式 
            base.AvaliableParameterNames.Add(Uid); 
            base.AvaliableParameterNames.Add(Signtime); 
            base.AvaliableParameterNames.Add(Appid); 
            base.AvaliableParameterNames.Add(Appversion); 
            base.AvaliableParameterNames.Add(Isaddapp); 
            base.AvaliableParameterNames.Add(Sessionkey); 
            base.AvaliableParameterNames.Add(Friendlist); 
            base.AvaliableParameterNames.Add(Signsumber); 
        } 
    }

 

 

 

 

public class WebConnectorContext 
    { 
        private List<WebClientWrapper> _asyncTasks; 
        private string baseAddress; 
        public WebConnectorContext(string baseAddress) 
        { 
            this.baseAddress = baseAddress; 
            init(); 
        } 
        private CookieContainer _cookie = new CookieContainer(); 
        private object _cookieDataLocker = new object(); 
        public CookieContainer AppCookie 
        { 
            get 
            { 
                lock (_cookieDataLocker) 
                { 
                    return _cookie; 
                } 
            } 
            protected set 
            { 
                lock (_cookieDataLocker) 
                { 
                    _cookie = value; 
                } 
            } 
        } 
        private void init() 
        { 
            _asyncTasks = new List<WebClientWrapper>(); 
        } 
        public virtual void AddMessageToSend(Message msg, Action<WebClientWrapper, string> action) 
        { 
            var task = new WebClientWrapper() 
                { 
                    Message = msg 
                }; 
            task.DownloadStringCompleted += (s) => OnResultReceived(task, s, action); 
            _asyncTasks.Add(task); 
            task.SendAsync(baseAddress, AppCookie); 
        } 
        private void onResultReceived(WebClientWrapper task, string e, Action<WebClientWrapper, string> action) 
        { 
            if(action != null) 
                action(task, e); 
            _asyncTasks.Remove(task); 
        } 
    }