首先是一个json序列化与反序列化的的帮助类（不记得是看博客园哪个大神的了。。）：

public class JsonHelper    {            public static string JsonSerializer
     
      (T t)          {            DataContractJsonSerializer ser = new DataContractJsonSerializer(typeof(T));            MemoryStream ms = new MemoryStream();            ser.WriteObject(ms, t);            string jsonString = Encoding.UTF8.GetString(ms.ToArray());            ms.Close();            return jsonString;        }        public static T JsonDeserialize
      
       (string jsonString)        {            DataContractJsonSerializer ser = new DataContractJsonSerializer(typeof(T));            MemoryStream ms = new MemoryStream(Encoding.UTF8.GetBytes(jsonString));            T obj = (T)ser.ReadObject(ms);            return obj;        }    }
      
     

一个实体类：

public class WeatherInfo    {        public string CityName { get; set; }        public string Date { get; set; }    }

 

服务端代码：

[WebMethod(Description = "返回信息")]        public string getJson(String city)        {            WeatherInfo weather = new WeatherInfo();            weather.CityName = city;            weather.Date = Date.Now.ToString();            string jsonString = JsonHelper.JsonSerializer
     
      (weather);            return jsonString;        }
     

客户端代码：

public void GetForecast(string city)        {            WebClient client = new WebClient();            client.OpenReadAsync(new Uri("http://localhost/Weather.asmx/getJson?city=" + city                + "&time=" + DateTime.Now.ToString("yyyyMMddHHmmss"),UriKind.RelativeOrAbsolute));            client.OpenReadCompleted += new OpenReadCompletedEventHandler(client_OpenReadCompleted);        }

void client_OpenReadCompleted(object sender, OpenReadCompletedEventArgs e)        {            try            {                XElement xmlWeather;                xmlWeather = XElement.Load(e.Result);                WeatherInfo weatherInfo = new WeatherInfo();                weatherInfo = JsonHelper.JsonDeserialize
     
      (xmlWeather.Value);                               //Debug.WriteLine(weatherInfo.CityName);            }            catch (Exception)            {                Deployment.Current.Dispatcher.BeginInvoke(() =>                {                    MessageBox.Show("数据获取出错。");                });            }        }
     

这样就实现了webservice相应wp7app请求并返回数据的过程。