比較兩個日期

Question

我如何比較兩個不同的日期，以找出哪些是以後的日子？例如，在date1我會下載一些數據之後存儲一個日期，並在date2，我將存儲當前的日期。然後我需要檢查哪一個更大/更晚：類似if(date1>date2)。

Answer 1

喜歡的東西：

NSDate* timeNow = [NSDate date]; 

    // If less than 30 seconds, do something 
    if ([timeNow timeIntervalSinceDate:anEarlierTime] < 30.0f) 
    { 
     // Do something 
    } 

Answer 2

可以使用的NSDate的比較：方法：

NSComparisonResult result = [Date2 compare:Date1]; 

if(result==NSOrderedAscending) 
    NSLog(@"Date1 is in the future"); 
else if(result==NSOrderedDescending) 
    NSLog(@"Date1 is in the past"); 
else 
    NSLog(@"Both dates are the same"); 

Answer 3

NSDateFormatter *df = [[NSDateFormatter alloc] init]; 
[df setDateFormat:@"yyyy-MM-dd"]; 
NSDate *dt1 = [[NSDate alloc] init]; 
NSDate *dt2 = [[NSDate alloc] init]; 
dt1 = [df dateFromString:@"2011-02-25"]; 
dt2 = [df dateFromString:@"2011-03-25"]; 
NSComparisonResult result = [dt1 compare:dt2]; 
switch (result) 
{ 
    case NSOrderedAscending: NSLog(@"%@ is greater than %@", dt2, dt1); break; 
    case NSOrderedDescending: NSLog(@"%@ is less %@", dt2, dt1); break; 
    case NSOrderedSame: NSLog(@"%@ is equal to %@", dt2, dt1); break; 
    default: NSLog(@"erorr dates %@, %@", dt2, dt1); break; 
} 

Answer 4

這是我用來與時區比較日期和我使用的是iOS 6的工作

 NSComparisonResult result = [timeStamp compare:serverDate]; 
     NSDateFormatter *df = [[NSDateFormatter alloc] init]; 
     [df setDateFormat:@"yyyy-MM-dd HH:mm:ss z"]; 
     switch (result) 
     { 
      case NSOrderedAscending: 
       NSLog(@"%@ is greater than %@", [df stringFromDate:serverDate], [df stringFromDate:timeStamp]); 
       break; 
      case NSOrderedDescending: 
       NSLog(@"%@ is less %@", [df stringFromDate:serverDate], [df stringFromDate:timeStamp]); 
       break; 
      case NSOrderedSame: 
       NSLog(@"%@ is equal to %@", [df stringFromDate:serverDate], [df stringFromDate:timeStamp]); 
       break; 
      default: 
       NSLog(@"erorr dates %@, %@", [df stringFromDate:serverDate], [df stringFromDate:timeStamp]); 
       break; 
     }