Files with VSDM extension are drawing files created with Microsoft Visio application that supports macros. VSDM files are OPC/XML drawings that are similar to VSDX, but also provide the capability to run macros when the file is opened.
Learn more about this file format here
GroupDocs.Conversion (in GroupDocs.Conversion.dll) Version: 22.214.171.124 (20.12)
public static readonly DiagramFileType Vsdm
Public Shared ReadOnly Vsdm As DiagramFileType
static initonly DiagramFileType^ Vsdm
static val Vsdm: DiagramFileType