mysqli_num_fields
result->field_count
(No version information available, might be only in CVS)
result->field_count — Get the number of fields in a result
说明
Procedural style:
int mysqli_num_fields
( mysqli_result $result
)
Object oriented style (property):
mysqli_result
int$field_count;
Returns the number of fields from specified result set.
参数
- result
-
Procedural style only: A result set identifier returned by mysqli_query(), mysqli_store_result() or mysqli_use_result().
返回值
The number of fields from a result set.
范例
Example#1 Object oriented style
<?php
$mysqli = new mysqli("localhost", "my_user", "my_password", "world");
/* check connection */
if (mysqli_connect_errno()) {
printf("Connect failed: %s\n", mysqli_connect_error());
exit();
}
if ($result = $mysqli->query("SELECT * FROM City ORDER BY ID LIMIT 1")) {
/* 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 */
$mysqli->close();
?>
Example#2 Procedural style
<?php
$link = mysqli_connect("localhost", "my_user", "my_password", "world");
/* check connection */
if (mysqli_connect_errno()) {
printf("Connect failed: %s\n", mysqli_connect_error());
exit();
}
if ($result = mysqli_query($link, "SELECT * FROM City ORDER BY ID LIMIT 1")) {
/* determine number of fields in result set */
$field_cnt = mysqli_num_fields($result);
printf("Result set has %d fields.\n", $field_cnt);
/* close result set */
mysqli_free_result($result);
}
/* close connection */
mysqli_close($link);
?>
上例将输出：
Result set has 5 fields.
