mysqli_field_count

mysqli->field_count()

(PHP 5)

mysqli->field_count() — Returns the number of columns for the most recent query

说明

Procedural style:

int mysqli_field_count ( mysqli $link )

Object oriented style (method):

mysqli_result

int field_count ( void )

Returns the number of columns for the most recent query on the connection represented by the link parameter. This function can be useful when using the mysqli_store_result() function to determine if the query should have produced a non-empty result set or not without knowing the nature of the query.

参数

link: Procedural style only: A link identifier returned by mysqli_connect() or mysqli_init()

返回值

An integer representing the number of fields in a result set.

范例

Example#1 Object oriented style


<?php
$mysqli = new mysqli("localhost", "my_user", "my_password", "test");

$mysqli->query( "DROP TABLE IF EXISTS friends");
$mysqli->query( "CREATE TABLE friends (id int, name varchar(20))");

$mysqli->query( "INSERT INTO friends VALUES (1,'Hartmut'), (2, 'Ulf')");


$mysqli->real_query($HTTP_POST_VARS['query']);

if ($mysqli->field_count) {
    /* this was a select/show or describe query */
    $result = $mysqli->store_result();

    /* process resultset */
    $row = $result->fetch_row();

    /* free resultset */
    $result->close();
}

/* close connection */
$mysqli->close();
?>

Example#2 Procedural style


<?php
$link = mysqli_connect("localhost", "my_user", "my_password", "test");

mysqli_query($link, "DROP TABLE IF EXISTS friends");
mysqli_query($link, "CREATE TABLE friends (id int, name varchar(20))");

mysqli_query($link, "INSERT INTO friends VALUES (1,'Hartmut'), (2, 'Ulf')");

mysqli_real_query($link, $HTTP_POST_VARS['query']);

if (mysqli_field_count($link)) {
    /* this was a select/show or describe query */
    $result = mysqli_store_result($link);

    /* process resultset */
    $row = mysqli_fetch_row($result);

    /* free resultset */
    mysqli_free_result($result);
}

/* close connection */
mysqli_close($link);
?>


	PHP5中文手册 mysqli_fetch mysqli_field_seek mysqli PHP Manual mysqli_field_count mysqli->field_count() (PHP 5) mysqli->field_count() — Returns the number of columns for the most recent query 说明 Procedural style: int mysqli_field_count ( mysqli `$link` ) Object oriented style (method): mysqli_result int field_count ( void ) Returns the number of columns for the most recent query on the connection represented by the `link` parameter. This function can be useful when using the mysqli_store_result() function to determine if the query should have produced a non-empty result set or not without knowing the nature of the query. 参数 `link` Procedural style only: A link identifier returned by mysqli_connect() or mysqli_init() 返回值 An integer representing the number of fields in a result set. 范例 Example#1 Object oriented style <?php $mysqli = new mysqli("localhost", "my_user", "my_password", "test"); $mysqli->query( "DROP TABLE IF EXISTS friends"); $mysqli->query( "CREATE TABLE friends (id int, name varchar(20))"); $mysqli->query( "INSERT INTO friends VALUES (1,'Hartmut'), (2, 'Ulf')"); $mysqli->real_query($HTTP_POST_VARS['query']); if ($mysqli->field_count) { /* this was a select/show or describe query / $result = $mysqli->store_result(); / process resultset / $row = $result->fetch_row(); / free resultset / $result->close(); } / close connection / $mysqli->close(); ?> Example#2 Procedural style* <?php $link = mysqli_connect("localhost", "my_user", "my_password", "test"); mysqli_query($link, "DROP TABLE IF EXISTS friends"); mysqli_query($link, "CREATE TABLE friends (id int, name varchar(20))"); mysqli_query($link, "INSERT INTO friends VALUES (1,'Hartmut'), (2, 'Ulf')"); mysqli_real_query($link, $HTTP_POST_VARS['query']); if (mysqli_field_count($link)) { /* this was a select/show or describe query / $result = mysqli_store_result($link); / process resultset / $row = mysqli_fetch_row($result); / free resultset / mysqli_free_result($result); } / close connection */ mysqli_close($link); ?> mysqli_fetch mysqli_field_seek mysqli PHP Manual