Converting VSD Drawings to PNGs – VBScript

This VBScript contains the logic to convert each drawing (page) of a specific Microsoft Visio file to a png named after its source page name and saves it to a target directory.

Option Explicit

' constants required for opening files in Visio
Const visOpenRO = 2
Const visOpenMinimized = 16
Const visOpenHidden = 64
Const visOpenMacrosDisabled = 128
Const visOpenNoWorkspace = 256

' constants required for setting ExportSize in Visio
Const visRasterFitToCustomSize = 3
Const visRasterPixel = 0


Sub export(filePath, exportDirectory, widthInPixels, heightInPixels)

    ' open file
    Dim visioApplication : Set visioApplication = CreateObject("Visio.Application")

    ' set export size
    visioApplication.Settings.SetRasterExportSize visRasterFitToCustomSize, widthInPixels, heightInPixels, visRasterPixel

    ' open document in Visio without showing it to the user
    visioApplication.Documents.OpenEx filePath, visOpenRO + visOpenMinimized + visOpenHidden + visOpenMacrosDisabled + visOpenNoWorkspace

    ' iterate over all pages and export each one
    Dim currentItemIndex
    For currentItemIndex = 1 To visioApplication.ActiveDocument.Pages.Count

        Dim currentItem : Set currentItem = visioApplication.ActiveDocument.Pages.Item(currentItemIndex)

        ' use the lowercase name for the file
        Dim exportPath : exportPath = exportDirectory & "\" & LCase(currentItem.Name) & ".png"

        ' export happens here!
    	currentItem.Export exportPath
    Next

    ' Quit Visio
    visioApplication.Quit
End Sub

' current directory
Dim currentDirectory : currentDirectory = CreateObject("Scripting.FileSystemObject").GetAbsolutePathName(".")

' file to open
Dim filePath : filePath = currentDirectory & "\AI - stundenplan.vsd"

' set export directory
Dim exportDirectory : exportDirectory = currentDirectory

export filePath, exportDirectory, 3557, 4114

Annotations about VBScript in general to better understand what is going on in this script.

• The colon (:) is the statement separator. This can be used to declare and assign a variable in one line.
• Use Dim NAME : NAME = VALUE for variables referencing not objects
• Use Set NAME = OBJECT for variables referencing objects
• Line Comments are started with '
• No parantheses are allowed for calling Subs (procedures) or Functions
• Stating Option Explicit at the first line requires each variable to be declared before it can be used
• To determine what parameters to set, you can use the record macro function in Visio. This button is not directly available in Visio 2010, refer to this guide on how to make it visible.
• The object explorer of Visio 2010 is very helpful to find the correct functions or procedures.
• Use the ampersand (&) to concatenate strings