THTTPReqResp Class

THTTPReqResp executes a method call on an invokable interface by sending a SOAP message to the server.

Pascal

THTTPReqResp = class(TComponent, IInterface, IWebNode, IHTTPReqResp);

C++

class THTTPReqResp : public TComponent, public IInterface, public IWebNode, public IHTTPReqResp;

File

SOAPHTTPTrans

Description

THTTPReqResp handles HTTP-based communication with a Web Service provider on behalf of a THTTPRio instance. THTTPRio uses this component to establish a connection to the Web Service provider and perform two tasks:

It can issue a "Get" request to obtain information from a WSDL document.

It can issue a "Post" request to pass a method call to the server for execution and retrieve the results.

The Web Service that is the target of these HTTP messages can be specified directly, using the SoapAction and URL properties, or it can be taken from the SoapAction in a WSDL document, as specified by the WSDLView property. Additional properties provide details that are included in the HTTP request message header.

Note: On Windows, THTTPReqResp uses WinInet to establish a connection to the server. Wininet.dll must be installed on the client system. wininet.dll is found in the Windows system directory if you have IE3 or higher installed. WinInet has the advantage that it provides support for secure connections (https). To use WinInet, compile your project without the USE_INDY symbol defined.

Note: On Linux, THTTPReqResp uses an internal instance of the Indy HTTP component (TIdHTTP) to communicate with the server. The Indy component has the advantage that it can be used from an application that acts as both client and server, whereas WinInet only works for pure client code. To use an internal TIdHTTP, compile your project with the USE_INDY symbol defined.