comparing the date in iphone

I have the date function.And I have to compare the previous date with current data in iphone

For current date I have code:-

NSDate* date = [NSDate date];

//Create the dateformatter object
NSDa开发者_如何学PythonteFormatter* formatter = [[[NSDateFormatter alloc] init] autorelease];

//Set the required date format
[formatter setDateFormat:@"yyyy-MM-dd"];

//Get the string date
NSString* str = [formatter stringFromDate:date];

//Display on the console
NSLog(str);

//Set in the lable
[dateLabel setText:str];

But I want to implement the compare the current date & previous date in iphone

Thanks in advance

You can compare dates using NSDate's comparison methods:

- (NSDate *)earlierDate:(NSDate *)anotherDate;
- (NSDate *)laterDate:(NSDate *)anotherDate;
- (NSComparisonResult)compare:(NSDate *)other;

- (BOOL)isEqualToDate:(NSDate *)otherDate;

Check NSDate class reference to know more..