Problem with comparing two QDateTime objects

[NoRulez]

Hey @all,

i've found a misterious problem, or is this thing a bug, or i have something miss unterstood.

I created an example where a function/slot is called on a specified date and time, but the time (QTime) doesn't equal at any time.
Here is the output:

Timer started
Date is equal
QTime("11:38:00") > QTime("11:37:57")
Date is equal
QTime("11:38:00") > QTime("11:37:58")
Date is equal
QTime("11:38:00") > QTime("11:37:59")
Date is equal
QTime("11:38:00") < QTime("11:38:00") =====> Here the time must also be equal, but why not?
Date is equal
QTime("11:38:00") < QTime("11:38:01")
Date is equal
QTime("11:38:00") < QTime("11:38:02")
Date is equal
QTime("11:38:00") < QTime("11:38:03")

And here is the source where i check these things:

Example::Example(QObject *parent) : QObject(parent) {
 dt.setDate(QDate(2008, 5, 15));
 dt.setTime(QTime(11, 38));
 int secs = 1;
 int msecs = secs * 1000;
    timer_check = new QTimer(this);
    connect(timer_check, SIGNAL(timeout()), SLOT(doSomething()));
    timer_check->start(msecs);
 cout << "Timer started" << endl;
}
 
Example::~Example() {
 
}
 
void Example::doSomething() {
 emit checkTime();
}
 
void Example::checkTime() {
 QDateTime dt_cur = QDateTime::currentDateTime();
 QTime t =  dt_cur.time();
 QDate d =  dt_cur.date();
 if(dt_cur == dt)
  cout << "Time reached ;-)" << endl;
 if(dt.date() == d) {
  cout << "Date is equal" << endl;
 }
 if(dt.time() == t) {
  cout << "Time is equal" << endl;
 }
 else {
  if(dt.time() > t)
   qDebug() << dt.time() << " > " << t;
  else if(dt.time() >= t)
   qDebug() << dt.time() << " >= " << t;
  else if(dt.time() < t)
   qDebug() << dt.time() << " < " << t;
  else if(dt.time() <= t)
   qDebug() << dt.time() << " <= " << t;
  else if(dt.time() == t)
   qDebug() << dt.time() << " == " << t;
  else
   qDebug() << dt.time() << " ?? " << t;
 }
}

Example::Example(QObject *parent) : QObject(parent) {
 dt.setDate(QDate(2008, 5, 15));
 dt.setTime(QTime(11, 38));
 int secs = 1;
 int msecs = secs * 1000;
    timer_check = new QTimer(this);
    connect(timer_check, SIGNAL(timeout()), SLOT(doSomething()));
    timer_check->start(msecs);
 cout << "Timer started" << endl;
}

Example::~Example() {

}

void Example::doSomething() {
 emit checkTime();
}

void Example::checkTime() {
 QDateTime dt_cur = QDateTime::currentDateTime();
 QTime t =  dt_cur.time();
 QDate d =  dt_cur.date();
 if(dt_cur == dt)
  cout << "Time reached ;-)" << endl;
 if(dt.date() == d) {
  cout << "Date is equal" << endl;
 }
 if(dt.time() == t) {
  cout << "Time is equal" << endl;
 }
 else {
  if(dt.time() > t)
   qDebug() << dt.time() << " > " << t;
  else if(dt.time() >= t)
   qDebug() << dt.time() << " >= " << t;
  else if(dt.time() < t)
   qDebug() << dt.time() << " < " << t;
  else if(dt.time() <= t)
   qDebug() << dt.time() << " <= " << t;
  else if(dt.time() == t)
   qDebug() << dt.time() << " == " << t;
  else
   qDebug() << dt.time() << " ?? " << t;
 }
}

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Why does the time/datetime doesn't match? Do I something wrong within the comparison?

Regards
NoRulez

[wysota]

According to me you are facing the same problem as comparing real numbers. QTime considers also miliseconds and you'll have a tough time trying to match them as well

You can overcome the problem by:

QTime t1;
QTime t2;
if(t2.secsTo(t1)==0){
  qDebug() << "Equal";
}

QTime t1;
QTime t2;
if(t2.secsTo(t1)==0){
  qDebug() << "Equal";
}

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