dbx_compare
(PHP 4 >= 4.1.0, PHP 5 < 5.1.0, PECL dbx >= 1.1.0)
dbx_compare — Compare two rows for sorting purposes
说明
dbx_compare (
array
$row_a ,
array $row_b ,
string $column_key [,
int $flags = DBX_CMP_ASC | DBX_CMP_NATIVE ] ) :
int
dbx_compare() is a helper function for dbx_sort() to ease the make and use of the custom sorting function.
参数
-
row_a -
First row
-
row_b -
Second row
-
column_key -
The compared column
-
flags -
The
flagscan be set to specify comparison direction:-
DBX_CMP_ASC- ascending order -
DBX_CMP_DESC- descending order
-
DBX_CMP_NATIVE- no type conversion -
DBX_CMP_TEXT- compare items as strings -
DBX_CMP_NUMBER- compare items numerically
-
返回值
Returns 0 if the row_a[$column_key] is equal to row_b[$column_key], and 1 or -1 if the former is greater or is smaller than the latter one, respectively, or vice versa if the flag is set to DBX_CMP_DESC.
范例
Example #1 dbx_compare() example
<?php
function user_re_order($a, $b)
{
$rv = dbx_compare($a, $b, "parentid", DBX_CMP_DESC);
if (!$rv) {
$rv = dbx_compare($a, $b, "id", DBX_CMP_NUMBER);
}
return $rv;
}
$link = dbx_connect(DBX_ODBC, "", "db", "username", "password")
or die("Could not connect");
$result = dbx_query($link, "SELECT id, parentid, description FROM table ORDER BY id");
// data in $result is now ordered by id
dbx_sort($result, "user_re_order");
// date in $result is now ordered by parentid (descending), then by id
dbx_close($link);
?>
