An append item format is a pattern used to append a field if there is no good match

public function setAppendItemFormat(
  int $field,
  string $value,
): void;

For example, suppose that the input skeleton is "GyyyyMMMd", and there is no matching pattern internally, but there is a pattern matching "yyyyMMMd", say "d-MM-yyyy". Then that pattern is used, plus the G. The way these two are conjoined is by using the AppendItemFormat for G (era). So if that value is, say "{0}, {1}" then the final resulting pattern is "d-MM-yyyy, G".

There are actually three available variables: {0} is the pattern so far, {1} is the element we are adding, and {2} is the name of the element.


  • int $field - Pattern field (see constants)
  • string $value - Pattern, such as "{0}, {1}"