A: Yes you can. Sample projects are included that demonstrate interactive terminal emulation applications in several development environments.
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A: Certainly. Although we provide a Telnet control for this purpose, any data source can be used (3rd party serial communications, data file, etc).
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A: Please visit http://www.celigne.co.uk/docs/vt220-rm/ to find programming information on the VT-series terminals.
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A: Instead of placing the VT control directly on the MDI Child Form, place a Panel object on the form, and then add the VT control to the panel.
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A: The VT control is not very useful for generating html that would be displayed in a browser, but it can work very well in “screen-scraping” mode. On your web server, use the Telnet control to access legacy data, feed it into the VT control as described in the previous question, and put the generated report into an edit box or table cell for display in the browser.
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A: Unfortunately, there is no consistent model for 3rd party component support across Office products and versions. The recommended usage in Excel is to use the product as a reference rather than inserting it as a control. Also, if the spreadsheet ever had a PowerTCP control inserted at any previous time, that data was cached by Excel and a new spreadsheet will be required. When deploying to users, please refer to "Distribution under Internet Information Server" in the documentation for instructions as the technique is the same.
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A: Microsoft Windows XP SP2 is a large update to the Windows XP operating system. The focus of this update is to tighten system security. One of those features is the built-in firewall. By default, Microsoft will turn on the firewall and block all applications from communicating over the Internet. As most PowerTCP products are designed for building Internet applications, those applications may be blocked from accessing the network. The solution to this problem, as it is for any application that needs to access the network, is to grant permission using Microsoft’s configuration utility. Instructions on using the Microsoft firewall are at http://www.microsoft.com/windowsxp/using/security/internet/sp2_wfintro.mspx, and more information about manual network security configuration is available by reading Microsoft Knowledge Base Article - 842242 . Also, Microsoft will disallow using ActiveX controls in Internet Explorer by default. It your web application uses PowerTCP ActiveX controls in IE, your users will have to manually adjust their security settings to allow ActiveX usage. If you find any other problems with SP2 and PowerTCP products, please contact Dart support at support@dart.com.
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A: There is a known bug in the .NET Framework that prevents ActiveX components from being licensed properly when they are dynamically instantiated. Currently, the workaround is to place the control on a form and instantiate an instance of that form without actually showing it. Microsoft is aware of the problem and we are currently looking at other workarounds for the problem.
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A: The following error has been experienced by some customers:

"The referenced component could not be found. Invalid Primitive Type: System.Reflection.Missing. Only CLS compliant primitive types can be used. Consider using CodeObjectCreateExpression."

SP3 for Framework 1.0 and SP1 for Framework 1.1 broke compatibility with some ActiveX controls. You need to download a hotfix from Microsoft.

Anyone you distribute your app to will also have to run this hotfix until Microsoft releases SP4 for Framework 1.0 and SP2 for Framework 1.1

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A: The problem is that a runtime license needs to be provided for the control. Resolution: Get LPK_TOOL.EXE from Microsoft. You can find it in their Cabinet Development kit. It is also on one of the CDs that comes with Visual Studio. Use the LPK_TOOL to create an .lpk file for YOUR control. We can't stress YOUR control enough. In other words, let's say that you have a control called MyControl that contains several Dart controls. When choosing the control in the LPK_TOOL listbox, choose MyControl, NOT the Dart Controls. Again, we can't stress this part enough as it is ALWAYS the part that is missed. Add the following to your document BEFORE any other objects are declared. Make sure LPKNAME.LPK is the name of YOUR lpk: <OBJECT CLASSID=clsid:5220cb21-c88d-11cf-b347-00aa00a28331> <PARAM NAME='LPKPath' VALUE='LPKNAME.LPK'>
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A: PowerTCP uses what is known as ClassFactory2 licensing. This is a system developed by Microsoft as part of the COM architecture. All of the major development environments that we use support this type of licensing when a control is placed on a form, however, only VB or VBA type environments support it when the control is 'created' without a form. By created, this means Dimming as New, not CreateObject. Of the other environments, we currently only provide direct support only for dynamic usage in Visual C++. See the component wrappers for the code needed to instantiate an object with a license. ( Example: ITcp.h and ITcp.cpp included with the sample projects ) If you absolutely HAVE to use our products in a project without a form, you will need to get direction from the company that makes the environment ( Example: Borland, Sybase ) on how to use COM objects that require ClassFactory2 licensing. If contacting them is not an option or is too costly, we may be able to assist you if you have one of the higher level support options or purchase incident support.
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A: Absolutely! We ship samples written in Delphi, PowerBuilder and PowerBuilder (in addition to Visual Basic 6, Visual Basic 7 (.NET), C++, and ASP). In addition, we have customers using our products in FoxPro, Cold Fusion, Java Script, and other “COM-enabled” environments.
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A: Unlike other environments, the interface is automatically disabled when the cursor changes to an hourglass in Powerbuilder.

Including the code below will allow the hourglass to persist, but it will not automatically disable the interface. To produce the usual hourglass behavior, the interface must be explicitely disabled and enabled by the user.

//In the external global function declarations
FUNCTION ulong SetCapture(ulong a) LIBRARY "user32.dll"
FUNCTION boolean ReleaseCapture()
LIBRARY "user32.dll"

//In the script
ulong ll_handle, ll_rc
ll_handle = Handle(this)
ll_rc = SetCapture(ll_handle)
SetPointer(hourglass!)

//after done
ReleaseCapture()

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A: Yes. Your trial download is identical to the purchased product. The only difference is the trial download will only work for 30 days (in the case of ActiveX products) or will work for 7 days between each rebuild (for .NET products).
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A: .NET COM interop is used to utilize this control within .NET, and a Visual Basic 7 sample is provided.
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A: Suppose you want to get a report and put it into a spread-sheet for your user to manipulate. In this scenario, the VT control can be created as an invisible control, you can use the invisible Telnet control to log into your host and send the commands needed to generate the report. As data arrives, you put it into the VT control. Then you simply read the Text property, parse the text, and put the relevant text into a spread-sheet control for display purposes. If you didn’t have the VT control, then you’d have to interpret the escape code sequences yourself, making this a very difficult process indeed.
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A: When using our controls in VBScript, you must specify optional parameters to prevent Type Mismatch errors.
For example, to zip a file with the FileStore, you need to create a SpanSettings instance:

Dim span
Set span = CreateObject("Dart.SpanSettings.1")
...
Zip1.FileStore.Zip("c:\Test\test.zip", span)
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A:

Yes, with reservations, particularly for server-side controls. Dart ActiveX controls require a message pump to process events. Unfortunately, .NET services do not implement a message pump. Therefore, server-side controls (Server, WebServer, FtpServer, etc) that require events to function cannot be used effectively in .NET services.

It may be possible for the user to implement a message pump on the application level in a .NET service.  We encourage our users to post working solutions on our forum.

Also, licensing of ActiveX controls in .NET requires the presence of the development license in the registry of the machine running the service.  The registry location of the license is:
HKEY_LOCAL_MACHINE / SOFTWARE / Dart / PowerTCP / License
This requirement is the same as for ASP deployment, and is further outlined on the Distribution page of the help file, under the heading "Distribution Under IIS."

As always, Dart controls can be used in a COM environment to develop Windows services (for example, with the PowerTCP Service control).

 

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A:

Yes, in most environments the ActiveX controls can be used in a scripting engine such as VBScript.

 

However, while the controls will work on 64 bit machines in compiled environments such as VB6 and VC++, they are limited to 32 bit Operating Systems in scripting environments.

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