Adobe has been saying that Flash can consume web service easily, it is, in fact, not totally right. when a service doesn’t have [WSDL], things get a bit different. To communicate with service that has no WSDL file, using PHP or other language to send request and then parse the response XML either using PHP or AS.
Here is what adobe says:
1. Macromedia Flash MX Professional 2004 has native support for SOAP and XML Remote Procedure Call (XML-RPC) web services.
2. You can consume SOAP-based web services with the WebServiceConnector component or by using the ActionScript WebService API. You can consume XML-RPC web services through the RPC ActionScript API, a lower-level API on which the SOAP API is based.
3. An alternative to a SOAP-based web service is a Representational State Transfer (REST) web service. A REST-based web service is different from SOAP in that calls to it incorporate the method name directly into the URI and pass parameters through a query string. The web service will return an XML response. The WebService API in Flash does not support REST-based web services. However, you can still consume them in Flash if you use a server-side script to connect to the web service and the Flash-native XML class to parse the XML response.
4. Under the SOAP umbrella, which includes the majority of web services available at the moment, Flash supports RPC-style and document-style web services. Remote Procedure Call (RPC) style means that the SOAP message formats for both requests and responses include a wrapper element containing the operation or method name. In document style, request and response SOAP messages do not contain this wrapper element. The two styles are distinguished in the WSDL by the style attribute within the soap:binding and/or the soap:operation tag. [ example here ]
5. Flash also does not support the import tag. You can use the import tag to keep parts of a WSDL description in separate files. You can reuse those parts, such as schemas and other definitions. Flash MX Professional 2004 does not support web services that use the import tag.
6. You may also run into problems with web services that require complex data, such as objects containing arrays, as an input parameter. If you try to pass complex data to a web service using the WebService API, you will receive an error saying that the endpoint URL could not be opened. To send complex data, use Flash Remoting. Complex data in output parameters, on the other hand, does not cause any problems.
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