How WēPO works from a web page

Introduction

The Print Wizard engine is available as an ActiveX component within our Web Print Object, also known as WēPO. Most all the functionality of the Print Wizard Engine is included in the ActiveX WēPO product, allowing a web server to "push" a print job out to a locally attached or a local network printer, keeping with our philosophy of printer-independent printing.

There are some key concepts that you should understand:

• WēPO is an ActiveX control, an ActiveX object that has a specific control or user display (the button), that has a specific action associated with it (click it and it prints). It can be displayed on a web page or within someone else's program or script. The actually display of the button can be hidden and only the action called (see the javascript examples below).
   
• WēPO, and other ActiveX objects, must be registered with Windows in order to be used. This requires several Windows registry entries and requires any program that wants to use this object, call it by a class id, differentiating it from other objects.
   
• An ActiveX object or control has associated with it an object name, "PWButtonX Control" in our case, and a file with an extension of either "ocx" or "dll".
   
• A cabinet, a file with the .cab extension, simply contains the ActiveX control or object and any necessary files, in a compressed file format.

The WēPO ActiveX object is called PwButtonXControl1 or "PwButtonX Control" and in most cases when downloaded and installed through Internet Explorer, the ActiveX control can be found in the default browser objects download directory: Also note that if you reference a .cab file, the .ocx file will appear after the cabinet file is decompressed.

C:\Windows\Downloaded Program Files\PwButtonXControl1.ocx

• Netscape, Opera, Mozilla, Firefox and Apple Safari may support ActiveX either directly with security options set properly, or with the addition of third party add-ons. Check out their web sites for more information.

WēPO code on your web page

By placing WēPO code on your web page, you can provide a method whereby the viewer of that web page can request a local print of a host resident print job, archived print job or a report stream through a server-side script request.

The primary part of this is to include the "object" request on the web page. Within this is the height and width of the button, the text of the button and any parameters for the button:

<OBJECT
      classid="clsid:4CE8026D-5DBF-48C9-B6E9-14A2B1974A3D"
      codebase="http://www.anzio.com/controls30/printwizocx.cab#version=3,0,0,0"
      width=50
      height=25
      align=center
      hspace=0     >
   <param name="mainurl" value="http://www.somewhere.com/myreport.pcl">
   <param name="caption" value="Print">
</OBJECT>

You can also set this to NOT show the print button, but rather to have a javascript or other web language script do the printing:

<OBJECT
      classid="clsid:4CE8026D-5DBF-48C9-B6E9-14A2B1974A3D"
      codebase="http://www.anzio.com/controls30/printwizocx.cab#version=3,0,0,0"
      width=0
      height=0
      align=center
      hspace=0     >
   <param name="mainurl" value="http://www.somewhere.com/myreport.pcl">
   <param name="caption" value="Print">
</OBJECT>

...
<input type=button value="my print" OnClick="javascript:buttonclick();">
...
<script language=javascript>
<!--
   function click(){
   document.Pwbuttonx1.Click();
}
//-->
</script>
...

You can set the "mainurl" parameter to retrieve any normal URL data from a web site and force it to the printer. With this, not only can you retrieve data securely through the HTTPS protocol, but you could retrieve data from a live feed by calling a server-side script. In this manner no file needs be present on the host to go fetch, rather data is delivered dynamically and directly to the user's printer.

...
<param name="mainurl" value="https://www.abc.com/cgi-bin/myquery?select=all>
...

WēPO supports secure web printing through the https SSL protocol

WēPO parameters for the web page

There are many parameters for the WēPO print object, allowing you to control the output of the print job. The table below defines most of these, check the WēPO section of the Print Wizard manual for a complete and up-to-date listing.

Accessing a web page with WēPO the first time

The first time you access a web page that contains a WēPO ActiveX Control, you will be asked to allow the Download of the control. In order to permit this under the latest versions of Windows, you must OK the first box and click on the security bar at the top. Click on "Install ActiveX Control..." to begin the install process.

At this point you will receive a second dialog box asking you to install the ActiveX component. Click "Install" and within a few seconds the download should finish and your page should display the control correctly.

If the dialogs mentioned above never appear, check your Internet Options and Advanced settings. It is possible that the options are set to automatically allow the ActiveX, or to never allow any client side add-ons.

What we have described above pertain to the default settings for Internet Explorer version 6 or later. Other versions and other web browsers may behave differently or not even allow ActiveX controls. See the Print Wizard and WēPO manual for more information.

Activating the control

With the latest Internet Explorer 6 patch releases and with Internet Explorer 7, an ActiveX control is NOT activated for use immediately. In order for you to utilize an ActiveX control, you must click twice. This can be a pain, but it is there partly for security reasons - so the user knows that an ActiveX control is being utilized.

Additionally, it is possible to get around this activation issue. You have two options:

• Use a javascript control that calls the PWButtonXControl1 control directly as in the example above
  
  
• Use an external, called script to control the object:

...
<br>
<script src="weposcript.js"></script>
...

where "weposcript.js" would read something like this:

document.write('<OBJECT ');
document.write('classid=
   "clsid:4CE8026D-5DBF-48C9-B6E9-14A2B1974A3D" ');
document.write('codebase=
   "http://www.anzio.com/controls30/printwizocx.cab#version=3,0,0,0" ');
document.write('width=50 ');
document.write('height=25 ');
document.write('align=center ');
document.write('hspace=0 ');
document.write('> ');
document.write('<param name="mainurl" value=
   "http://www.abc.com/myreport.txt">');
document.write('<param name="caption" value="Print">');
document.write('<param name="Cancel" value="0">');
document.write('<param name="Default" value="0">');
document.write('<param name="DragCursor" value="-12">');
document.write('<param name="DragMode" value="0">');
document.write('<param name="Enabled" value="-1">');
document.write('<param name="Font" value="MS Sans Serif">');
document.write('<param name="Visible" value="-1">');
document.write('<param name="DoubleBuffered" value="0">');
document.write('<param name="Cursor" value="0">');
document.write('<param name="licensecode" value>');
document.write('<param name="charset" value>');
document.write('<param name="debug" value="0">');
document.write('<param name="initfile" value>');
document.write('<param name="orientation" value>');
document.write('<param name="duplex" value>');
document.write('<param name="fontname" value>');
document.write('<param name="overlay" value>');
document.write('<param name="bitmap" value>');
document.write('<param name="faxnum" value>');
document.write('<param name="printersetup" value="0">');
document.write('</OBJECT>');

For some reason known only to Microsoft, you can do the external script approach, but you cannot directly control the object from within a javascript function located on the same page. While this works to show the control, it still requires a double click to activate. It must be an external script to get around the double click activation issue.

Managing WēPO through the browser

Installing and registering WēPO

There is no pre-installation process available from within a web browser for WēPO. You can install and register the ActiveX control all from a web page that calls that object. If the dialogs mentioned above never appear when you first access a page with a WēPO control on it, check your Internet Options and Advanced settings. It is possible that these are either set to automatically allow the ActiveX, or to never allow any client side add-ons.

Disabling and uninstalling WēPO

From within your browser it is possible to manage your "add-ons" and either disable or delete them from use. This is done through the Tools menu Internet Options (also available under the Windows Control Panel). Under the Programs tab, click on "Manage add-ons...".

From here you can select the correct control, "PwButtonX Control" and disable or delete it.

When you "delete" the add-on, it removes the proper Windows registry entries (the object registration information) and deletes the file from the specified area.

When "disabled" the WēPO ActiveX control does not display properly and cannot be double clicked to activate, but is still registered in Windows and found in the download directory.

Managing WēPO through Windows

The WēPO ActiveX object can also be managed through Windows itself, either via the Control Panel or through console command-line driven applications.

Installing and registering WēPO

At present there is no manual procedure for installation of the WēPO object. However, you can register the object manually from a command line prompt or a script. To do this you would use the "regsvr32.exe" program:

regsvr32 c:\MyDirectory\PwButtonXControl1.ocx

This will correctly register the WēPO object for use by web pages, pointing to your directory of choice.

Uninstalling and unregistering WēPO

You can unregister the object and uninstall WēPO from the Internet Options dialog in Windows (found in the Control Panel and done exactly as above through your browser).

You can also manually unregister WēPO through the "regsvr32.exe" program and then manually remove the "ocx" file from the disk. To do this enter the following:

regsvr32 -u c:\MyDirectory\PwButtonXControl1.ocx

How Windows handles WēPO internally

Upon first trying to use this, Internet Explorer 6 and Internet Explorer 7 will warn you that the web page needs to download and install an ActiveX. Browser's top bar needs to be right-clicked on to allow download and may need a second click to install (or you will need to verify Install from a download dialog by clicking OK). Once you do this, the object is then registered in the Windows registry automatically for use by the web browser.

There have been reports that with some browsers and with certain browser settings in effect, if you once deny this install, then the next time you come to this page it will be assumed to not allow it and no security bar message pops up.

Various browser behave differently and may locate files in other directories or registry entries, but the concept is the same.

When installed the first time through a browser, the WēPO object (the file name will be PwButtonXControl1.ocx) resides in

C:\Windows\Download Program Files\

With new releases and changes in class-id, there would thus be a conflict. Windows changes the directory name for these conflicts, with duplicate files ending up in

C:\Windows\Download Program Files\CONFLICT.1,
C:\Windows\Download Program Files\CONFLICT.2, ...

If you have conflicts, the ocx in the latest CONFLICT.x appears to get used, i.e. CONFLICT.2 and you can actually remove the others without any problems.

Also on initial setup, the following registry entries point to this ActiveX file:

\My Computer\HKEY_CLASSES_ROOT\CLSID\{4CE8026D-...\

\My Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{4CE8026D-...\

\My Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\
   CurrentVersion\ModuleUsage\C:/Windows/Downloaded Program Files/CONFLICT.1

(and other pointers to other CONFLICTs if they exist with OCX)

\My Computer\HKEY_LOCAL|MACHINE\SOFTWARE\Microsoft\CurrentVersion\SharedDLLs

When you delete a registered ActiveX component from within the Internet Options "Manage add-ons" dialog, the registry entries are first removed and then the object file is deleted from disk. The "regsvr32.exe -u ..." will unregister the ActiveX object as well (it just does not automatically remove it from disk).