ios - If statement with dates -

what trying make if statement dates using greater less signs. reason greater sign works. here code:

nsdate *currdate = [nsdate date]; nsdateformatter *dateformatter = [[nsdateformatter alloc]init]; [dateformatter setdateformat:@"hhmm"]; nsstring *datestring = [dateformatter stringfromdate:currdate]; nslog(@"%@",datestring);  if (datestring < @"0810" && datestring > @"0800") {     nslog(@"homeroom"); } else {     nslog(@"no"); } 

the output code if time 8:03:

2013-04-08 08:03:47.956 schedule2.0[13200:c07] 0803 2013-04-08 08:03:47.957 schedule2.0[13200:c07] no 

if make greater sign this:

if (datestring > @"0800") {     nslog(@"homeroom");  } else {     nslog(@"no"); } 

the output this:

2013-04-08 08:03:29.748 schedule2.0[14994:c07] 0803 2013-04-08 08:03:29.749 schedule2.0[14994:c07] homeroom 

create nsdate object time 8:10 , 1 8:00. can compare given date both these dates

if(([date0800 compare:date] == nsorderingascending) && [date0810 compare:date] == nsorderingdescending) ) {     // date between other } 

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to create boundaries dates can this

nsdate *date = [nsdate date]; // nsdatecomponents *components = [[nscalendar currentcalendar] components:( nsyearcalendarunit | nsmonthcalendarunit | nsdaycalendarunit ) fromdate:date]; components.hour = 8; components.minute = 0;  nsdate *date0800 = [[nscalendar currentcalendar] datefromcomponents: components]; components.minute = 10; nsdate *date0810 = [[nscalendar currentcalendar] datefromcomponents: components]; 

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if insist of using operators < , >, can use timeinterval of date objects.

if(([date0800 timeintervalsince1970] < [date timeintervalsince1970]) && ([date0810 timeintervalsince1970] > [date timeintervalsince1970])) {     // date lays between other 2 } 

but beware of checking == on it, faulty due rounding errors.