array_multisort() can be used to
sort several arrays at once or a multi-dimensional array
according by one of more dimensions. It maintains key
association when sorting.
The input arrays are treated as columns of a table to be
sorted by rows - this resembles the functionality of SQL
ORDER BY clause. The first array is the primary one to sort
by. The rows (values) in that array that compare the same are
sorted by the next input array, and so on.
The argument structure of this function is a bit
unusual, but flexible. The very first argument has to be an
array. Subsequently, each argument can be either an array or
a sorting flag from the following lists.
Sorting order flags:
Sorting type flags:
No two sorting flags of the same type can be specified
after each array. The sorting flags specified after an array
argument apply only to that array - they are reset to default
SORT_ASC and SORT_REGULAR before each new array argument.
成功回傳TRUE失敗回傳FALSE。
In this example, after sorting, the first array will
contain 10, "a", 100, 100. The second array will contain 1,
1, "2", 3. The entries in the second array corresponding to
the identical entries in the first array (100 and 100) were
sorted as well.
In this example, after sorting, the first array will
contain 10, 100, 100, "a" (it was sorted as strings in
ascending order), and the second one will contain 1, 3, "2",
1 (sorted as numbers, in descending order).