Maintaining Plug-Ins and Opening a Structure: IDocs 
Prerequisites
You have created a form with Visual Basic. You have launched the SAPforms Designer as a Visual Basic add-in and are in the main window. The form controls are shown in the table displayed in the bottom control.
Procedure
Maintain Plug-Ins
The Options dialog box of the SAPforms Designer is then displayed.
Enter
SAPforms Data Plug-In for IDoc in the SAPData Plug-In.
The value in the SAPforms Plug-In box is set by default according to the form development environment you are using. If you are using the stand-alone version of the SAPforms Designer, you must also maintain this plug-in.
Opening a Structure
A dialog box is then displayed in which you can choose whether you want to retrieve an IDoc description from the R/3 System via RFC (From R/3) or import it from a local file (From File).
You can only import the description from a local file if you have already exported it from the R/3 System.

Accessing the local file is the faster option. For more information see
generating IDocsWhen you select this the top control is divided in two. You can now display an instance of your IDoc structure in the right-hand control.
Result
The segment description of the IDoc is exported from R/3 and displayed as a tree in the top left-hand control in the main SAPforms Designer window.