startup.vrp.annotated

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Program constants.

DclConst OPEN_FOR_READ_ONLY Value(0)
DclConst READ_OK Value(0)
DclConst TEXT_FILE_EOF Value(15) 
DclConst CRLF Value(x'0D0A')
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All globals and constants declared in the startup program are globally available to all forms and programs. One convention to consider is to prefix variables declared in the startup program is to prefix those variables especially intended for use by any form or program is to prefix them. In this case, anytime any form or program references a field that starts with 'Global_' you know that field is declared, and stored, here. 

DclFld Global_CustomerName Type(*String)
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Not used by this program here for a discussion point. DclDS Global FldScope(Local) DclDSFld CustomerName Type(Char) Len(40) Start(1) DclDSFld CustomerAddress Type(*Char) Len(35) Start(41)


    

  

  

  

    

      

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Read the notes.txt file so it can be shown in the main form.
The text file is being read and loaded in this startup program because if its 
loaded in the form itself there is a slight, but annoying flicker, as the textbox 
is refreshed. Loading it ensures the form is fully populated and read to go when
it is displayed. 

    

    

      
ReadTextFile()

    

  

  

  

    

      

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Show the main form.

    

    

      
Show formMain

    

  

  

  

    

      

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Read the notes.txt file and put its contents in the formMain.textboxDocs
textbox. 

    

    

      
BegSr ReadTextFile 
    DclFld StatusCode Type(*Integer) Len(4) 
    DclFld Line Type(*String)

    

  

  

  

    

      

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Open the file.

    

    

      
    StatusCode = formMain.osFileMain.open ('Notes.txt',OPEN_FOR_READ_ONLY) 
    If (StatusCode <> READ_OK)

    

  

  

  

    

      

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Show error message if open failed.

    

    

      
        MsgBox Msg('Notes.txt file couldn''t be opened.') 
        LeaveSr 
    EndIf

    

  

  

  

    

      

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Clear the target textbox. 

    

    

      
    formMain.textboxDocs.Text = *Blanks

    

  

  

  

    

      

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Do a prime-the-pump read.

    

    

      
    StatusCode = formMain.osFileMain.ReadLine(Line)

    

  

  

  

    

      

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Do until end of file...

    

    

      
    DoWhile StatusCode <> TEXT_FILE_EOF

    

  

  

  

    

      

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Append the line of text read from the file to the textbox, appending
a CRLF to each line.

    

    

      
        formMain.textboxDocs.Text = formMain.textboxDocs.Text + Line + CRLF

    

  

  

  

    

      

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Attempt to read another line.

    

    

      
        StatusCode = formMain.osFileMain.ReadLine(Line) 
    EndDo

    

  

  

  

    

      

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Close the file.

    

    

      
    formMain.osFileMain.Close()
EndSr