Android访问WCF服务

Posted 2022-03-04 alex80

原文链接：http://www.cnblogs.com/VinC/archive/2011/02/24/1964049.html

 

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.

示例代码下载

 

 

 

此部分分为 建立Http请求 跟 接受WCF 返回的数据.

一. 建立Http请求的方法

protected String getRequest(String url, DefaultHttpClient client)
            throws Exception 
        String result = null;
        int statusCode = 0;
        HttpGet getMethod = new HttpGet(url);
        Log.d(TAG, "do the getRequest,url=" + url + "");
        try 
            getMethod.setHeader("User-Agent", USER_AGENT);
            // HttpParams params = new HttpParams();

            // 添加用户密码验证信息
            // client.getCredentialsProvider().setCredentials(
            // new AuthScope(null, -1),
            // new UsernamePasswordCredentials(mUsername, mPassword));

            HttpResponse httpResponse = client.execute(getMethod);
            // statusCode == 200 正常
            statusCode = httpResponse.getStatusLine().getStatusCode();
            Log.d(TAG, "statuscode = " + statusCode);
            // 处理返回的httpResponse信息
            result = retrieveInputStream(httpResponse.getEntity());
         catch (Exception e) 
            Log.e(TAG, e.getMessage());
            throw new Exception(e);
         finally 
            getMethod.abort();
        
        return result;
    

 

参数URL: 我们要请求的地址

Client:  这个可以直接用new DefaultHttpClient(new BasicHttpParams()) 来初始化.

这个方法中需要注意RetrieveInputStream方法, 这个是当Http请求完成之后, 用来处理服务器返回数据的方法,

 

二. 接受从WCF端传回的数据

protected  String retrieveInputStream(HttpEntity httpEntity) 
        int  length = (int) httpEntity.getContentLength();
        if  (length < 0)
            length = 10000;
        StringBuffer stringBuffer = new  StringBuffer(length);
        try  
            InputStreamReader inputStreamReader = new  InputStreamReader(
                    httpEntity.getContent(), HTTP.UTF_8);
            char  buffer[] = new char[length];
            int  count;
            while  ((count = inputStreamReader.read(buffer, 0, length - 1)) > 0) 
                stringBuffer.append(buffer, 0, count);
            
         catch  (UnsupportedEncodingException e) 
            Log.e(TAG, e.getMessage());
         catch  (IllegalStateException e) 
            Log.e(TAG, e.getMessage());
         catch  (IOException e) 
            Log.e(TAG, e.getMessage());
        
        return  stringBuffer.toString();
    

此方法在接受到WCF服务端返回的数据之后,  转换程String类型返回.

附加内容:

请求数据之前封装方法:

    private static final String BASE_URL = "http://10.0.2.2:82/BlogCategoryService/";
    private static final String EXTENSION = "Json/";;
    private static final String TAG = "API";
    private static final String USER_AGENT = "Mozilla/4.5";

    public JSONObject getObject(String sbj) throws JSONException, Exception 
        return new JSONObject(getRequest(BASE_URL + EXTENSION + sbj));
    

    public JSONArray getArray(String sbj) throws JSONException,
            Exception 
        return new JSONArray(getRequest(BASE_URL + EXTENSION + sbj));
    

    protected String getRequest(String url) throws Exception 
        return getRequest(url, new DefaultHttpClient(new BasicHttpParams()));
    

 

 

总结 ： 此篇主要说明了Http请求的的两个阶段, 建立请求跟接受服务器返回的数据, 在下篇再主要说明如何处理服务端返回的JSON数据,并把数据显示在UI上面.