It takes up to four parameters and returns the first one of them that is defined (not null) and not empty.
That is, the first one that is defined (not null) and not empty. It takes up to four parameters and returns the first one that has any content.
It takes up to four parameters and returns the first one that has any content. That is, the first one that is defined (not null) and not empty.
It takes up to four parameters and returns the first one that has any content. That is, the first one that is defined (not null) and not empty.