为什么字符串中的NSDate少了一天？

Question

if I try:

NSDateFormatter* formatter = [[NSDateFormatter alloc] init];
[formatter setDateFormat:@"yyyyMMdd"];

and

[formatter dateFromString:@"20120423"];

My new NSDate object will be: 2012 04 22 . Why one day less?

Thank

Answer 1

您遇到时区问题，可以通过添加以下代码来解决：

formatter.timeZone = [NSTimeZone timeZoneWithName:@"GMT"];

Answer 2

For those who looks for swift 3 version

let formatter        = DateFormatter()
formatter.timezone   = TimeZone(abbreviation: "GMT")
formatter.dateFormat = "yyyyMMdd"
formatter.date(from: "20120423")

Answer 3

对于使用Swift 3的一个衬垫

Date.init(dateString: "2014-07-31", format: "yyyy-MM-dd", timeZone: TimeZone.init(abbreviation: "GMT")!)