OFN_LONGNAMES top-level constant
int
const OFN_LONGNAMES
For old-style dialog boxes, this flag causes the dialog box to use long file names. If this flag is not specified, or if the OFN_ALLOWMULTISELECT flag is also set, old-style dialog boxes use short file names (8.3 format) for file names with spaces. Explorer-style dialog boxes ignore this flag and always display long file names.
Implementation
const OFN_LONGNAMES = 0x00200000;