无法设置wxDateTime日，月和年

Question

I am trying a very simple code for "licence expiry check". However, the following bit is always taking me to the first condition, ie, expired, although I set the month to June. I cannot seem to figure out what the problem is. I would really appreciate some help.

LicDMY.LicDate = wxDateTime::Today(); 
LicDMY.TDay = wxDateTime::Today();
LicDMY.LicDate.SetYear(2019);
LicDMY.LicDate.SetMonth(wxDateTime::Jun);
LicDMY.LicDate.SetDay(30);
if(LicDMY.LicDate.IsEarlierThan(LicDMY.TDay)||LicDMY.LicDate.IsEqualTo(LicDMY.TDay))
    message = new wxStaticText(this, wxID_ANY, wxT("Expired! Renew License \n"));
else
    message = new wxStaticText(this, wxID_ANY, wxT("Welcome! \n"));

Answer 1

Calling wxDateTime::SetMonth(wxDateTime::Jun) would make the object invalid when its current day is 31, as it happens on Jan 31, when this question was asked. You could exchange the order of SetDay() and SetMonth() calls to make this work or, preferably, just use Set(30, wxDateTime::Jun, 2019) to change the entire date part at once or even write LicDate = wxDateTime(30, wxDateTime::Jun, 2019) which might be more readable.

Finally, it looks like you are not using debug facilities of wxWidgets (ie compile your code with NDEBUG defined) as otherwise you would have been immediately notified about the problem because you would have got an assertion failure with the message saying that assert "(0 < day) && (day <= GetNumberOfDays(month, year))" failed in Set(): Invalid date in wxDateTime::Set() . It is strongly recommended that you do use them, this is very helpful during development and will catch a lot of errors in your use of wxWidgets API.