RAD Studio VCL Reference
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TWebConnection Class

TWebConnection uses HTTP to manage the connection to an application server.

Pascal
TWebConnection = class(TStreamedConnection, ITransport);
C++
class TWebConnection : public TStreamedConnection, public ITransport;

SConnect

TWebConnection is used in the client portion of a multi-tiered database application to establish and maintain the connection between the client and a remote application server. The Web connection object can 

Establish an initial connection to a remote application server. 

Obtain an IAppServer for the application server. 

Obtain a list of providers on the application server. 

Drop the connection to the remote application server. 

TWebConnection establishes the initial connection between the client application and a remote application server using HTTP. To use TWebConnection, you must have the following: 

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. 

The server system must have IIS version 4 or better or Netscape Enterprise version 3.6 or better. 

HTTPsrvr.dll must be installed with the Web server to which TWebConnection forms a connection. HTTPsrvr.dll launches the application server and marshals all calls to the application server interface. 

Once the connection is established, the client registers any or all of its client datasets, and these client datasets use the IAppServer interface from the Web connection component to communicate with providers on the application server, or to otherwise call the application server's data module interface. 

To connect to remote application servers using DCOM, use the TDCOMConnection component instead. To connect to remote application servers using TCP/IP, use the TSocketConnection component instead. To connect to remote application servers using SOAP, use the TSoapConnection component. 

 

TDataSetProvider 

TClientDataSet 

TDCOMConnection 

TRemoteDataModule 

IAppServer 

TSocketConnection 

TSoapConnection 

Extending the Interface of the Application Server 

Specifying a Connection Using HTTP

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