Converting time string to Date format iOS

问题

I have a string @"21:57" and I want to save it with the same HH:mm format in NSDate. I tried converting it using:

NSDateFormatter *dateFormatter = [[NSDateFormatter alloc]init];
dateFormatter.dateFormat = @"HH:mm";
NSDate *date  = [dateFormatter dateFromString:stringToConvertFrom];

but I'm getting 2000-01-01 21:57:00 +0000 instead of 21:57.

来源：https://stackoverflow.com/questions/18724190/converting-time-string-to-date-format-ios