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# NSDateTimeOrdering

Key for the string that specifies how to use ambiguous numbers in date strings.

```
extern NSString * const NSDateTimeOrdering;
```

## Discussion

Specify this value as a permutation of the letters M (month), D (day), Y (year), and H (hour). For example, MDYH treats “2/3/01 10” as the 3rd day of February 2001 at 10:00 am, whereas DMYH treats the same value as the 2nd day of March 2001 at 10:00 am. If fewer numbers are specified than are needed, the numbers are prioritized to satisfy day first, then month, and then year. For example, if you supply only the value 12, it means the 12th day of this month in this year because the day must be specified. If you supply “2 12” it means either February 12 or December 2, depending on if the ordering is “MDYH” or “DMYH.”

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