Aspose::Cells::Style::SetCultureCustom method. Gets and sets the culture-dependent pattern string for number format. If no number format has been set for this object, null will be returned. If number format is builtin, the pattern string corresponding to the builtin number will be returned in C++....the pattern content(such as, one builtin date format is “m/d/y”...the pattern content(such as, one builtin date format is “m/d/y”...