i18n\Formatter $dateFormat

The default format string to be used to format a date. This can be "short", "medium", "long", or "full", which represents a preset format of different lengths.

It can also be a custom format as specified in the ICU manual. Alternatively this can be a string prefixed with php: representing a format that can be recognized by the PHP date()-function.

For example:

'MM/dd/yyyy' // date in ICU format
'php:m/d/Y' // the same date in PHP format