Window.AcceptFileDrop

From Xojo Documentation

Method

Window.AcceptFileDrop(FileType as String)

Supported for all project types and targets.

Permits documents of type FileType to be dropped on the window.

Notes

FileType must be a file type you specified via the FileType class or the File Type Sets Editor. It works correctly even if you have multiple file types defined with the same File type code, and you don't specifically call AcceptFileDrop for the first such type.