iPhone: Convert date string to a relative time stamp
cocoa, datetime, iphone, objective-c, time
Solution
-(NSString *)dateDiff:(NSString *)origDate {
NSDateFormatter *df = [[NSDateFormatter alloc] init];
[df setFormatterBehavior:NSDateFormatterBehavior10_4];
[df setDateFormat:@"EEE, dd MMM yy HH:mm:ss VVVV"];
NSDate *convertedDate = [df dateFromString:origDate];
[df release];
NSDate *todayDate = [NSDate date];
double ti = [convertedDate timeIntervalSinceDate:todayDate];
ti = ti * -1;
if(ti < 1) {
return @"never";
} else if (ti < 60) {
return @"less than a minute ago";
} else if (ti < 3600) {
int diff = round(ti / 60);
return [NSString stringWithFormat:@"%d minutes ago", diff];
} else if (ti < 86400) {
int diff = round(ti / 60 / 60);
return[NSString stringWithFormat:@"%d hours ago", diff];
} else if (ti < 2629743) {
int diff = round(ti / 60 / 60 / 24);
return[NSString stringWithFormat:@"%d days ago", diff];
} else {
return @"never";
}
}
Problem
I've got a timestamp as a string like: Thu, 21 May 09 19:10:09 -0700 and I'd like to convert it to a relative time stamp like '20 minutes ago' or '3 days ago'. What's the best way to do this using Objective-C for the iPhone?