(PECL maxdb >= 1.0)
maxdb_num_fields -- maxdb_result->field_count — Get the number of fields in a result
过程化风格
面向对象风格
maxdb_num_fields() returns the number of fields from specified result set.
The number of fields from a result set
Example #1 Object oriented style
<?php
$maxdb = new maxdb("localhost", "MONA", "RED", "DEMODB");
/* check connection */
if (maxdb_connect_errno()) {
printf("Connect failed: %s\n", maxdb_connect_error());
exit();
}
if ($result = $maxdb->query("SELECT * FROM hotel.city ORDER BY zip")) {
/* determine number of fields in result set */
$field_cnt = $result->field_count;
printf("Result set has %d fields.\n", $field_cnt);
/* close result set */
$result->close();
}
/* close connection */
$maxdb->close();
?>
Example #2 Procedural style
<?php
$link = maxdb_connect("localhost", "MONA", "RED", "DEMODB");
/* check connection */
if (maxdb_connect_errno()) {
printf("Connect failed: %s\n", maxdb_connect_error());
exit();
}
if ($result = maxdb_query($link, "SELECT * FROM hotel.city ORDER BY zip")) {
/* determine number of fields in result set */
$field_cnt = maxdb_num_fields($result);
printf("Result set has %d fields.\n", $field_cnt);
/* close result set */
maxdb_free_result($result);
}
/* close connection */
maxdb_close($link);
?>
以上例程的输出类似于：
Result set has 3 fields.