Symbian学习笔记(17)-51CTO.COM

如何使用Symbian中提供的WebService框架来SayHello。

　　从SDK文档中提供的资料来看这个接口似乎有点复杂，包括了Connection API、Description API和Manager API三套东西，此外还涉到了XML的解析之类的一些API的应用。

　　阅读了一下它的例子程序(S60Ex目录下的AddressBook)，让我更晕乎了。怎么跟自己平时使用的WebService不一样了?

　　在SDK文档中关于CSenServiceConnection有这么一段描述：

　　Web Services包括两种不同的框架模型:

　　1. Identity Based Web Services Framework (ID-WSF). The framework ID for this is KDefaultIdWsfFrameworkID ("ID-WSF").

　　2. Basic Web Services Framework. Framework ID is KDefaultBasicWebServicesFrameworkID ("WS-I").

　　如果提供了Contract则缺省使用ID-WSF。

　　首先用.NET做一个简单的WebServices来测试，就用缺省产生的HelloWorld吧。很简单的，它的SOAP描述如下：

view plaincopy to clipboardprint?
<PRE class=csharp name="code">POST /uim/PService.asmx HTTP/1.1

Host: localhost

Content-Type: text/xml; charset=utf-8

Content-Length: length

SOAPAction: "urn:pservice:helloworld"

<?xml version="1.0" encoding="utf-8"?>

<soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">
<soap:Body>

<HelloWorld xmlns="http://sharetop/pservice" />

</soap:Body>

</soap:Envelope>

HTTP/1.1 200 OK

Content-Type: text/xml; charset=utf-8

Content-Length: length

<?xml version="1.0" encoding="utf-8"?>

<soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">

  <soap:Body>

<HelloWorldResponse xmlns="http://sharetop/pservice">
<HelloWorldResult>string</HelloWorldResult>
  </HelloWorldResponse>

  </soap:Body>

</soap:Envelope></PRE>

view plaincopy to clipboardprint?

POST /uim/PService.asmx HTTP/1.1
Host: localhost
Content-Type: text/xml; charset=utf-8

Content-Length: length

SOAPAction: "urn:pservice:helloworld"

<?xml version="1.0" encoding="utf-8"?>

<soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">

<soap:Body>

<HelloWorld xmlns="http://sharetop/pservice" />

</soap:Body>

</soap:Envelope>

HTTP/1.1 200 OK

Content-Type: text/xml; charset=utf-8

Content-Length: length

<?xml version="1.0" encoding="utf-8"?>

<soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">

  <soap:Body>

<HelloWorldResponse xmlns="http://sharetop/pservice">

<HelloWorldResult>string</HelloWorldResult>

</HelloWorldResponse>

</soap:Body>

</soap:Envelope>

POST /uim/PService.asmx HTTP/1.1

Host: localhost

Content-Type: text/xml; charset=utf-8

Content-Length: length

SOAPAction: "urn:pservice:helloworld"
<?xml version="1.0" encoding="utf-8"?>
<soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">
  <soap:Body>
<HelloWorld xmlns="http://sharetop/pservice" />
  </soap:Body>
</soap:Envelope>
HTTP/1.1 200 OK
Content-Type: text/xml; charset=utf-8
Content-Length: length
<?xml version="1.0" encoding="utf-8"?>
<soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">
  <soap:Body>
<HelloWorldResponse xmlns="http://sharetop/pservice">
   <HelloWorldResult>string</HelloWorldResult>
</HelloWorldResponse>
  </soap:Body>
</soap:Envelope>

　　下面我们自己来做一个WS的客户端实例吧。先用向导生成一个HelloWorld应用，为了研究方便，我们不打算做什么界面，所有的输出都通过LOG输出到日志文件。

　　为了编码方便，我们增加一个类WebEngine，它应该派生于CSenBaseFragment和MSenServiceConsumer。声明如下：

view plaincopy to clipboardprint?

class CWebEngine : public CSenBaseFragment, public MSenServiceConsumer

{

public:

  ~CWebEngine();
static CWebEngine* NewL();
  static CWebEngine* NewLC();

void ConnectL();

void SayHello();

//from MSenServiceConsumer

  virtual void HandleMessageL(const TDesC8& aMessage);

virtual void HandleErrorL(const TInt aErrorCode,const TDesC8& aError);

  virtual void SetStatus(const TInt aStatus);

protected:

//from CSenBaseFragment

virtual void StartElementL(const TDesC8& aNsUri, const TDesC8& aLocalName, const TDesC8& aQName, const Xml::RAttributeArray& aAttrs);

  virtual void EndElementL(const TDesC8& aNsUri,  const TDesC8& aLocalName, const TDesC8& aQName);

private:

CWebEngine();

void ConstructL();

public:

CHelloWorldResult * delegate;

private:

  CSenServiceConnection* iConnection;

CSenXmlServiceDescription* iSession;

CSenXmlReader* iXmlReader;

};

class CWebEngine : public CSenBaseFragment, public MSenServiceConsumer

{

public:

~CWebEngine();

static CWebEngine* NewL();

static CWebEngine* NewLC();

void ConnectL();

void SayHello();

//from MSenServiceConsumer

virtual void HandleMessageL(const TDesC8& aMessage);

virtual void HandleErrorL(const TInt aErrorCode,const TDesC8& aError);

virtual void SetStatus(const TInt aStatus);

protected:

//from CSenBaseFragment

virtual void StartElementL(const TDesC8& aNsUri, const TDesC8& aLocalName, const TDesC8& aQName, const Xml::RAttributeArray& aAttrs);

virtual void EndElementL(const TDesC8& aNsUri,  const TDesC8& aLocalName, const TDesC8& aQName);

private:

CWebEngine();

void ConstructL();

public:

CHelloWorldResult * delegate;

private:

CSenServiceConnection* iConnection;

CSenXmlServiceDescription* iSession;

CSenXmlReader* iXmlReader;

};

　　除了实现两个父类的方法以外，还要增加ConnectL()用来连接，SayHello()用来调用远程方法。那个delegate是一个 CHelloWorldResult类的实例，这个类同样派生于CSenDomFragment，说明它对应一段XML内容，我们用它来处理结果，就是那个HelloWorldResponse标签下的内容。

　　这个WebEngine的实现逻辑是：先在ConnectL中初始化WS客户端，在SetStatus回调中取当前状态值如果为 KSenConnectionStatusReady ，则可以调用SayHello去执行那个WS的方法，然后，在HandleMessageL回调中将得到的结果(XML内容的字节流)去解析一下，解析 XML的回调就是那两个StartElement和EndElement。

【编辑推荐】