格式未知时创建PHP DateTime

With the help of this question, I have been able to parse a date string into a DateTime object, then display it in the desired format. The DateTime constructor works well in deciphering DateTime strings with one (very understandable) exception - it cannot tell the difference between dd/mm/YYYY and mm/dd/YYYY.

If I do the following:

$dt = new DateTime("05/03/1900"); // 5th march 1900
echo $dt->format('Y-m-d');

Then I get the following output:

1900-05-03

However, the original date is in dd/mm/YYYY format, so my output is incorrect - I now have the 3rd May 1900.

Is there a way to set DateTime to prefer dd/mm/YYYY over mm/dd/YYYY when parsing a date string?

Edit: I am calling date_default_timezone_set('Europe/London'); in the constructor of this class but this doesn't seem to have any effect. Perhaps this isn't linked to the DateTime class.

You can use the DateTime::createFromFormat

$dt = DateTime::createFromFormat( 'd/m/Y', '05/03/1900' );
echo $dt->format( 'Y-m-d' );