iOS NSDate 要增加月份 或 往前推月份

現在NSDate

NSDate *newdate = [NSDate date];

1.增加月份

NSDateComponents* dateComponents = [[NSDateComponents alloc]init];
[dateComponents setMonth:1];
NSCalendar* calendar = [NSCalendar currentCalendar];
NSDate* newDate = [calendar dateByAddingComponents:dateComponents toDate:“這邊填寫目前的NSDate” options:0];

1.減少月份

NSDateComponents* dateComponents = [[NSDateComponents alloc]init];
[dateComponents setMonth:-1];
NSCalendar* calendar = [NSCalendar currentCalendar];
NSDate* newDate = [calendar dateByAddingComponents:dateComponents toDate:“這邊填寫目前的NSDate” options:0];