如何将本地时间转化为"指定时区"的时间

NSDateFormatter *formatter =[[NSDateFormatter alloc] init];
[formatter setDateFormat:@"yyyy-MM-dd hh:mm:ss"];
NSTimeZone* timeZone = [NSTimeZone timeZoneWithName:@"Asia/Shanghai"];
[formatter setTimeZone:timeZone];
NSString *loctime = [formatter stringFromDate:date];
[formatter release];
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不管用户如何设置,,均获得24小时显示(其中的HH,强制指定为24时制)
NSDateFormatter * formatter =[[NSDateFormatter alloc] init];
[formatter setDateFormat:@"yyyy-MM-dd HH:mm:ss"];
NSString *loctime = [formatter stringFromDate:date];
[formatter release]