SftTree/OCX 7.0

Using SftTree/OCX with Internet Explorer

Softel vdm, Inc.

The SftTree/OCX control can be used directly on web pages, as long as Internet Explorer is used as the browser platform.

Due to some limitations and the typeless nature of VBScript, the special control "SftTree/OCX 7.0 Tree Control (IE)" must be used for Internet Explorer/VBScript support. VBScript only allows Variant parameters to return values.  This typically limits the usefulness of most other ActiveX controls. By providing a special version of SftTree/OCX, this restriction does not apply to SftTree/OCX.

This special control properly supports control events by passing Variant parameters so these can be modified by the application. In addition, all control methods have been extended to support Variant parameters when needed (e.g., Cell.GetPosition offers Variant return values).

All picture-related properties (based on loaded files) must be set at run-time. If these are defined at design-time, they will be lost once the page is saved. This is a limitation of the property bag implementation used by HTML/IE.

Overview

SftTree/OCX can be added to web pages. Using HTML design tools, such as Microsoft FrontPage or ActiveX Control Pad, SftTree/OCX can be added to a web page and controlled using a scripting language such as VBScript.

Depending on the development environment used, the steps necessary to add an ActiveX control to a web page differ. See your development environment for specific instructions.

The SftTree/OCX installation automatically registers the design-time version of SftTree/OCX with the system. Most development tools offer a tool bar or a list of available ActiveX controls. The SftTree/OCX control may not automatically appear on these tool bars or in the list of available controls. Additional steps may be required; see your development environment for specific instructions.

All SftTree/OCX controls are installed in the Windows System(32) directory. When distributing (i.e. placing web pages on a server), you need to place a cabinet file on your server. A cabinet file is a compressed file containing SftTree/OCX along with the required digital signature, marking the control as a safe control.

Designing a Web Page

Any ActiveX-enabled web page design tool can be used (such as Microsoft FrontPage or Microsoft's ActiveX Control Pad). Please see the documentation that was supplied with your preferred development tool for specific information about ActiveX control use.

The ActiveX control can be manipulated using VBScript or any other suitable language.

When an ActiveX control is inserted into a web page, the <OBJECT> tag is used to describe the control and its properties.

<object classid="clsid:0DE0AC03-8141-4ea3-8FDF-4960C261F680" id="SftTreeIE1" width="272" height="289"
        CODEBASE="SftTree_IX86_I_70.cab#version=7,0,0,0">
    <param name="PropVer" value="60">
    <param name="_cx" value="7197">
    <param name="_cy" value="7646">
    <param name="PropFile" value>
    ... more ...
</object>

If a user doesn't have the control installed on his or her system, the CODEBASE keyword of the OBJECT tag must be specified, so that the control can be downloaded from your web server. Downloading the control is fully automatic when it is used for the first time.

Digital Signature

The SftTree/OCX control contained in the provided cabinet files is digitally signed so that users can safely browse your web pages.  Users who browse a web page containing a SftTree/OCX control will receive a digital certificate when the control is used for the very first time.  This certificate assures that the control and the associated file have not been tampered with and that the control can be used safely.  The SftTree/OCX control passes all security checks, even if a user has changed the security settings to the highest level possible.

Note:  You cannot alter or suppress this certificate. If the control file SftTree_IX86_I_70.cab is altered or tampered with in any way, an appropriate warning message is issued.

This certificate has been issued by a certification authority (Verisign).  To find out more about certificates and certification authorities, please visit www.microsoft.com or www.verisign.com.  Without such a certificate, many users would not be able to view a web page containing an ActiveX control, because their web browser settings would reject the page as containing unsafe content.

The certificate is only shown once.  When a user accesses other web pages which also make use of the same ActiveX control, the certificate is NOT displayed.

CODEBASE

When inserting a SftTree/OCX control into a web page, code similar to the following is used.  Make sure to update the CODEBASE keyword so it contains the correct relative or absolute path to the SftTree/OCX cabinet file.  Also, to insure that users of your web page have the correct minimum version of SftTree/OCX installed, use the version= keyword as shown in this example.

<object classid="clsid:0DE0AC03-8141-4ea3-8FDF-4960C261F680" id="SftTreeIE1" width="272" height="289"
        CODEBASE="SftTree_IX86_I_70.cab#version=7,0,0,0">
    <param name="PropVer" value="60">
    <param name="_cx" value="7197">
    <param name="_cy" value="7646">
    <param name="PropFile" value>
    ... more ...
</object>

The correct version can be found in the release notice that was installed in the SftTree OCX 7.0 program group.

Design-Time

To design a web page with a SftTree/OCX control and to manipulate the control properties, a tool such as Microsoft's FrontPage or ActiveX Control Pad is used.  A design-time version of SftTree/OCX (the file SftTree_IX86_I_70.ocx) is registered and used for this purpose.

When SftTree/OCX is installed, this design-time version is automatically registered with the system.  Program entries to register and unregister this version are supplied in the group SftTree OCX 7.0.  You can test your web page and the automatic installation of the ActiveX control by unregistering the design time version using the entry Maintenance, Unregister SftTree OCX from Windows Registry.

If the control is not registered, the next access to a web page will automatically download the run-time version of the ActiveX control (provided the correct CODEBASE keyword is used).

Only one version of SftTree/OCX can be registered at any given time.  By registering the design-time version, the run-time version is no longer accessible and vice versa.  After downloading the run-time version, you will have to reinstate the design-time version using the Maintenance, Register SftTree OCX in Windows Registry entry.

Run-Time

To test the automatic downloading of SftTree/OCX controls, it may be necessary to unregister all versions of SftTree/OCX from your system.  The design-time and run-time versions of SftTree/OCX can be unregistered using program entries in the group SftTree OCX 7.0.

After an automatic download has taken place and you would like to repeat the test (maybe because of modifications to the web page), unregister the ActiveX control by using the entry Maintenance, Unregister SftTree OCX from Windows Registry.

If the control is not registered, the next access to a web page will automatically download the run-time version of the ActiveX control (provided the correct CODEBASE keyword is used).

Only one version of SftTree/OCX can be registered at any given time.  By registering the design-time version, the run-time version is no longer accessible and vice versa.  After downloading the run-time version, you will have to reinstate the design-time version using the Maintenance, Register SftTree OCX in Windows Registry entry.

Common Errors

When using SftTree/OCX, please keep in mind that Internet browsers (such as Internet Explorer) may not generate error messages when a web page contains errors or invalid HTML syntax.  This may prevent an ActiveX control from being shown or VBScript and JavaScript code may fail without any indication as to the source of the error.

Incorrect relative or absolute path names to files (such as the CODEBASE keyword) can cause a web page to fail without an error message.


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