htmlCgi

htmlCgi
CGI (Common Gateway Interface) server class

Description

htmlCgi is derived from htmlServer and manages the Common Gateway Interface between the server and the html++ application. The CGI standard is widely support among nearly all web server vendors. htmlCgi is commonly used on Unix platforms but is also compatible with Windows-based servers such as O'Reilly WebSite and others.

The counterpart class to htmlCgi is htmlISAPI, which interfaces html++ applications directly to any ISAPI-compliant web server, such as Microsoft IIS.

htmlCgi and htmlISAPI behave and are used identically to their htmlServer parent class, with the only exception being the constructor arguments.

Declaration

#include <dcmicro/htmlpp/cgi.h>

Hierarchy

See Also

htmlServer, htmlISAPI, CNVList, htmlForm, htmlInputHidden, htmlCookie

Related Constants/Definitions

None.

Constructors

htmlCgi()

Constructs an empty, uninitialized cgi object, loading environment variables into the member variables. This constructor is rarely used, and must be followed by a manual call to the base-class Initialize() method.

htmlCgi( istream& is )

Constructs the cgi object from the is input stream, loading environment variables into the member variables. Implicitly executes the Initialize() method, passing along is as the argument. Typically, the standard C++ cin input stream object is used.

Destructors

virtual ~htmlCgi()

Destroys the object.

Member Methods and Member Variables

Refer to htmlServer.

Example Use
See Also: Tutorial : Advanced Topics : Decoding Content From Other Sources

The following two programs illustrate use of the htmlCgi class to pass data from a form (generated using html++, though it could be any HTML form document) to a server-side html++ application. The application then processes the data and outputs a dynamically-generated page.

// program 1: Create the data input form

#include <stdio.h>

#include <stdlib.h>

#include <dcmicro/htmlpp/htmlpp.h>

int main( void )

{

   htmlCgi    server ;

   htmlPage   page( "html++ form input example" ) ;

   //  Create a form, setting the action

   //  statement to "/cgi-bin/formdemo"

   htmlForm   form( "/cgi-bin/formdemo" );

   //  Set up input areas for last name,

   //  first name, and email address. Allow

   //  up to 20 characters for the names,

   //  and 30 characters for the email.

   form << "Last Name: "

        << htmlInputText( "lname", 20 )

        << htmlBreak() ;

   form << "First Name: "

        << htmlInputText( "fname", 20 )

        << htmlBreak() ;

   form << "Email address: "

        << htmlInputText( "email", 30 )

        << htmlBreak() ;

   //  Add a submit button with a custom label

   form << htmlCenter( htmlInputSubmit("Press to continue") );

   page << form ;

   server << page ;

   return 0 ;

}

// program 2: formdemo.cpp - Process the form data

#include <stdio.h>

#include <stdlib.h>

#include <dcmicro/htmlpp/htmlpp.h>

int main( void )

{

   htmlPage   page( "html++ formdemo.cpp application" ) ;

   //  Construct an htmlCgi object to receive

   //  the CGI form data from standard input.

   htmlCgi  server( cin ) ;

   //  Output a few data items from the

   //  server environment.

   page << "Server_Software: " << server.Server_Software

        << htmlBreak()

        << "Server_Name: " << server.Server_Name

        << htmlBreak()

        << "Gateway_Interface: " << server.Gateway_Interface

        << htmlBreak()

        << "Request_Method: " << server.Request_Method

        << htmlBreak()

        << "Remote_Host: " << server.Remote_Host

        << htmlParagraph() ;

   //  Output all CGI data from the form

   String  name ;

   String  value ;

   Boolean good_data = server.Enumerate( name, value, TRUE ) ;

   while ( good_data )

   {

      page << htmlBold( name )

           << " : "

           << value

           << htmlBreak() ;

      //  loop for next form field

      good_data = server.Enumerate( name, value ) ;

   }

   server << page ;

   return 0 ;

}

Program 1 Output

Content-Type: text/html

<HTML>

<HEAD>

<TITLE>html++ form input example</TITLE>

</HEAD>

<BODY>

<FORM ACTION="/cgi-bin/formdemo" METHOD="POST">

Last Name: <INPUT TYPE="TEXT" NAME="lname" SIZE="20"><BR>

First Name: <INPUT TYPE="TEXT" NAME="fname" SIZE="20"><BR>

Email address: <INPUT TYPE="TEXT" NAME="email" SIZE="30"><BR>

<CENTER><INPUT TYPE="SUBMIT" VALUE="Press to continue"></CENTER></FORM>

</BODY>

</HTML>

Program 2 (formdemo.cpp) Output

Content-Type: text/html

<HTML>

<HEAD>

<TITLE>html++ formdemo.cpp application</TITLE>

</HEAD>

<BODY>

Server_Software: Stronghold/2.0.1 Apache/1.2b11<BR>

Server_Name: www.dcmicro.com<BR>

Gateway_Interface: CGI/1.1<BR>

Request_Method: POST<BR>

Remote_Host: rangelan.connectup.com<P></P>

<B>lname</B> : Smith<BR>

<B>fname</B> : John<BR>

<B>email</B> : jsmith@anywhere.com<BR>

</BODY>

</HTML>

©1998 DC Micro Development. All rights reserved.
No portion of this document may be c opied or reproduced without expressed written consent.
html++ is a trademark of DC Micro Development.

	htmlCgi is derived from htmlServer and manages the Common Gateway Interface between the server and the html++ application. The CGI standard is widely support among nearly all web server vendors. htmlCgi is commonly used on Unix platforms but is also compatible with Windows-based servers such as O'Reilly WebSite and others.

	The counterpart class to htmlCgi is htmlISAPI, which interfaces html++ applications directly to any ISAPI-compliant web server, such as Microsoft IIS.

	htmlCgi and htmlISAPI behave and are used identically to their htmlServer parent class, with the only exception being the constructor arguments.

	htmlServer, htmlISAPI, CNVList, htmlForm, htmlInputHidden, htmlCookie

	Constructs an empty, uninitialized cgi object, loading environment variables into the member variables. This constructor is rarely used, and must be followed by a manual call to the base-class Initialize() method.

	Constructs the cgi object from the is input stream, loading environment variables into the member variables. Implicitly executes the Initialize() method, passing along is as the argument. Typically, the standard C++ cin input stream object is used.

	The following two programs illustrate use of the htmlCgi class to pass data from a form (generated using html++, though it could be any HTML form document) to a server-side html++ application. The application then processes the data and outputs a dynamically-generated page.

	// program 1: Create the data input form
	#include <stdio.h>
	#include <stdlib.h>
	#include <dcmicro/htmlpp/htmlpp.h>

	int main( void )
	{
	htmlCgi server ;
	htmlPage page( "html++ form input example" ) ;

	// Create a form, setting the action
	// statement to "/cgi-bin/formdemo"
	htmlForm form( "/cgi-bin/formdemo" );

	// Set up input areas for last name,
	// first name, and email address. Allow
	// up to 20 characters for the names,
	// and 30 characters for the email.
	form << "Last Name: "
	<< htmlInputText( "lname", 20 )
	<< htmlBreak() ;

	form << "First Name: "
	<< htmlInputText( "fname", 20 )
	<< htmlBreak() ;

	form << "Email address: "
	<< htmlInputText( "email", 30 )
	<< htmlBreak() ;

	// Add a submit button with a custom label
	form << htmlCenter( htmlInputSubmit("Press to continue") );

	page << form ;

	server << page ;
	return 0 ;
	}


	// program 2: formdemo.cpp - Process the form data
	#include <stdio.h>
	#include <stdlib.h>
	#include <dcmicro/htmlpp/htmlpp.h>

	int main( void )
	{
	htmlPage page( "html++ formdemo.cpp application" ) ;

	// Construct an htmlCgi object to receive
	// the CGI form data from standard input.
	htmlCgi server( cin ) ;

	// Output a few data items from the
	// server environment.
	page << "Server_Software: " << server.Server_Software
	<< htmlBreak()
	<< "Server_Name: " << server.Server_Name
	<< htmlBreak()
	<< "Gateway_Interface: " << server.Gateway_Interface
	<< htmlBreak()
	<< "Request_Method: " << server.Request_Method
	<< htmlBreak()
	<< "Remote_Host: " << server.Remote_Host
	<< htmlParagraph() ;

	// Output all CGI data from the form
	String name ;
	String value ;
	Boolean good_data = server.Enumerate( name, value, TRUE ) ;
	while ( good_data )
	{
	page << htmlBold( name )
	<< " : "
	<< value
	<< htmlBreak() ;

	// loop for next form field
	good_data = server.Enumerate( name, value ) ;
	}

	server << page ;
	return 0 ;
	}


	Content-Type: text/html
	<HTML>
	<HEAD>
	<TITLE>html++ form input example</TITLE>
	</HEAD>
	<BODY>
	<FORM ACTION="/cgi-bin/formdemo" METHOD="POST">
	Last Name: <INPUT TYPE="TEXT" NAME="lname" SIZE="20"><BR>
	First Name: <INPUT TYPE="TEXT" NAME="fname" SIZE="20"><BR>
	Email address: <INPUT TYPE="TEXT" NAME="email" SIZE="30"><BR>
	<CENTER><INPUT TYPE="SUBMIT" VALUE="Press to continue"></CENTER></FORM>
	</BODY>
	</HTML>