VCHANGEFIELD is often misunderstood. When called correctly it is a great 
upgrade to any VPLUS application, but it is not a requirement.
I often use VCHANGEFIELDS to hide fields by changing to Ftype to "D" and 
Enh to "NONE", then to "O" and "HI" to unhide.
For VCHANGEFIELDS you use negative numbers to address fields in screen 
order (left>right, top>bottom), or the positive field number.

Another option instead of using VCHANGEFIELDS is to use Parent/child forms.
The various child forms must be identical buffer len and field count, 
with the exception of Ftype's and Enhancements.
Call VGETNEXTFORM using the child form name, and VSHOWFORM to accomplish 
the same effect as VCHANGEFIELDS.

You usually don't need to know the fields names for a basic VPLUS 
application.
Unless you're planning on writing a generic routine to process any given 
form, then you may want to look at calling VGETFORMINFO & VGETFIELDINFO

What are you trying to accomplish?
I might be able to dig up an old COBOL/VPLUS examples.



On 10/22/2013 11:34 PM, Paul Richards wrote:
> Michael: thanks for that. It appears that changing to upper-case has got me over that particular error message. In reply to your other email I can load the form file and the form via ENTRY -  I needed to do this in order to get the field names for the COBOL program.
>
> So the program gets past recognizing the form file and form  I'm now getting an error: "A field with the screen order supplied does not exist". I presume this refers to a section of 7 entries (7 fields on the form) thus:
>
> multiply screen-order of field-entry (1) by -1
> giving field-id of spec-entry (1)
> move 5 to change-type of spec-entry (1)
> move "O" to change-spec of spec-entry (1) .... etc
>
> The comments in the program state: "Screen order is indicated to field change intrinsic as a negative number".
>
> As you have probably guessed I'm stumbling my way through VPLUS so I'm not really sure what these entries do.
>
> So I've either got an incorrect screen order or may be the program doesn't recognize my field names - I used the VPLUS entry field names in the program.
>

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