CHttpServer::CallFunction

virtual int CallFunction( CHttpServerContext* pCtxt, LPTSTR pszQuery, LPTSTR pszCommand );

Return Value

A value of one of the following enum types:

Enum value	Description
callOK	The function call was successful.
callParamRequired	A required parameter was missing.
callBadParamCount	There were too many or too few parameters.
callBadCommand	The command name was not found.
callNoStackSpace	No stack space was available.
callNoStream	No CHtmlStream was available.
callMissingQuote	A parameter had a bad format.
callMissingParams	No parameters were available.
callBadParam	A parameter had a bad format (i.e., only one quote).

Parameters

pCtxt

Pointer to a CHttpServerContext object.

pszQuery

A pointer to a query. Specific to the type of command received from the client. See Remarks for more information.

pszCommand

Either a pointer to a query or NULL. Specific to the type of command received from the client. See Remarks for more information.

Remarks

Called by the framework to find and execute the appropriate function associated with the command in the URL.

Below is a breakdown between the types of methods received and the parameters:

Method type	*pszQuery*	*pszCommand*
GET	A pointer to the EXTENSION_CONTROL_BLOCK structure query string.	NULL
POST	A pointer to a query sent in the body of the command.	Pointer to the EXTENSION_CONTROL_BLOCK structure query string.

Note Fill-out forms authors are advised to use only the POST method because of browser inconsistencies, and because GET methods are limited to a 1024-byte buffer. When writing forms for ISAPI, either use only the POST method, or design the ISA so that only the default function handles the form.

For example, some browsers sending a form via GET with an action of:

TestLet.DLL?Command

will truncate Command and send:

TestLet.DLL?name=value

instead of the correct command:

TestLet.DLL?Command?name=value

By truncating Command, the browser removes the association to the ISA function needed to map the request. Unless the function Command is the default function, the form will not be handled correctly.

If you want to handle parsing of the EXTENSION_CONTROL_BLOCK structure function lpszQueryString yourself, override CallFunction and do not use the PARSE_MAP macros. See Internet Server API (ISAPI) Parse Maps for more information on using the parse map macros.

CHttpServer Overview | Class Members | Hierarchy Chart