本章目的: 用Wcf建立可以上Android可以访问的数据服务, 数据传输格式采用比较适合于移动互联网传输的Json格式.
服务的开发流程我们按照 服务契约(ServiceContract), 服务实现(Service), 实体对象模型(Model) 及服务发布的流程来介绍.
由于自己对Http请求的链接认识的比较浅,对于有些问题没法做出清楚明了的解释, Android访问WCF这篇文章我会贴出来代码, 让后说明一下关注的地方, 不做深入研究.
一. 服务契约(Contract)
[ServiceContract] public interface IAccountJsonService { [OperationContract(Name = "GetAccountDataJson")] [WebGet(RequestFormat = WebMessageFormat.Json, ResponseFormat = WebMessageFormat.Json, UriTemplate = "GetAccountData", BodyStyle = WebMessageBodyStyle.Bare)] List<Account> GetAccountData(); [OperationContract(Name = "SendMessageJson")] [WebInvoke(Method = "GET", ResponseFormat = WebMessageFormat.Json, UriTemplate = "SendMessage/{Message}", BodyStyle = WebMessageBodyStyle.Bare)] string SendMessage(string Message); }
此契约定义了两个方法, GetAccountData(获取Account数据列表, 方法不带参数), SendMessage, 获取从客户端传过来的数据, 并返回;
1. 这里面注意WebInvoke(SendMessage方法)这个Attribute, Method代表了Http的访问方法, 我们这是从服务器获取数据,是请求数据, 所以用GET, 这个也可以用另外一个Attribute来替代-WebGet(GetAccountData方法);
2. 我们要给客户端返回Json数据,我们只需在WebInvoke or WebGet Attribute中指定ResponseFormat的格式即可, 这个从名字命名就可以看出来是制定返回的数据格式的.
3. 要注意UriTemplate属性, 这个是指定我们请求时的方法路径, 后面给出示例.
二. 服务实现(Service)
public class AccountService : IAccountJsonService { public List<Account> GetAccountData() { return MockAccount.AccountList; } public string SendMessage(string Message) { return " Message:" + Message; } }
此处只是实现了IAccountJsonService接口.
三. 实体对象模型&模拟数据
实体类定义:
[DataContract] public class Account { [DataMember] public string Name { get; set; } [DataMember] public int Age { get; set; } [DataMember] public string Address { get; set; } [DataMember] public DateTime Birthday { get; set; } }
模拟数据:
public class MockAccount { public static List<Account> AccountList { get { var list = new List<Account>(); list.Add(new Account { Name = "Bill Gates", Address = "YouYi East Road", Age = 56, Birthday = DateTime.Now }); list.Add(new Account { Name = "Steve Paul Jobs", Address = "YouYi West Road", Age = 57, Birthday = DateTime.Now }); list.Add(new Account { Name = "John D. Rockefeller", Address = "YouYi North Road", Age = 65, Birthday = DateTime.Now }); return list; } } }
模拟数据返回一个Account的列表, 含有三条模拟数据, Birthday用DateTime.Now可是随时查看数据是不是最新生成的.
四. 服务发布
在这个例子里面, 我们的服务采用Console的发布形式, 如果采用IIS发布, 只要参考WCF的服务配置信息, 在IIS环境下配置就OK了.
WCF配置信息
<system.serviceModel> <behaviors> <serviceBehaviors> <behavior name=""> <serviceMetadata httpGetUrl="mex" httpGetEnabled="true"/> <serviceDebug httpHelpPageEnabled="true" includeExceptionDetailInFaults="true"/> </behavior> </serviceBehaviors> <endpointBehaviors> <behavior name="WebHttpBindingBehavior"> <webHttp/> </behavior> </endpointBehaviors> </behaviors> <services> <service name="Hosting.AccountService"> <endpoint address="xml" binding="webHttpBinding" contract="Hosting.IAccountXmlService" behaviorConfiguration="WebHttpBindingBehavior"/> <!--<endpoint address="json" binding="webHttpBinding" contract="Hosting.IAccountJsonService" behaviorConfiguration="WebHttpBindingBehavior"/>--> <host> <baseAddresses> <add baseAddress="http://127.0.0.1:82/AccountService"/> </baseAddresses> </host> </service> </services> </system.serviceModel>
控制台进行服务的托管发布
class Program { static void Main(string[] args) { using (ServiceHost host = new ServiceHost(typeof(AccountService))) { host.Open(); Console.WriteLine("AccountService Address:"); foreach (var endpoint in host.Description.Endpoints) { Console.WriteLine(endpoint.Address.ToString()); } Console.WriteLine("AccountService Started,Press any key to stop service..."); Console.ReadKey(); host.Close(); } } }
下篇将介绍Android如何访问我们编写的服务.