在PHP 5.5中以月为单位使用DateTime的最大限制

Question

I was reading this

and I am not sure if twelfth is the maximum for ordinal values.

The reason is I want to do something like

$startDate = new \\DateTime('twenty-third day of this month');

and I am not sure what's the maximum limit for the ordinal value for the day part of the month.

Answer 1

As of php 7.0.4 twelfth is the "largest" ordinal supported:

/* The relative text table. */
static timelib_lookup_table const timelib_reltext_lookup[] = {
    { "first",    0,  1 },
    { "next",     0,  1 },
    { "second",   0,  2 },
    { "third",    0,  3 },
    { "fourth",   0,  4 },
    { "fifth",    0,  5 },
    { "sixth",    0,  6 },
    { "seventh",  0,  7 },
    { "eight",    0,  8 },
    { "eighth",   0,  8 },
    { "ninth",    0,  9 },
    { "tenth",    0, 10 },
    { "eleventh", 0, 11 },
    { "twelfth",  0, 12 },
    { "last",     0, -1 },
    { "previous", 0, -1 },
    { "this",     1,  0 },
    { NULL,       1,  0 }
};