Question

How can I convert Visio binary file (.vsd extension) to Visio xml file(.vdx extension) in programming?

Does Microsoft provide such C/C++ library ?

Answer 1

Option 1: Use Visio application programmatically

Any .NET language can control Visio through it’s COM automation interfaces and use its SaveAs method.

$visio = New-Object -ComObject Visio.InvisibleApp;
$visio.Documents.Open(".\Drawing.vsd");
$visio.Documents.SaveAs(".\Drawing.vdx");
$visio.Quit();

SaveAs method on MSDN

This option, obviously requires the Visio application to be installed.

Option 2: Use a third party library

I’ve never used it but apparently Aspose.Diagram for .NET can be used to convert these files.

Microsoft Library?

To answer your last question: No, Microsoft does not provide a C/C++ library to perform this conversion.