©
本文檔使用 php中文網手册 發布
(PHP 5)
mysqli::$field_count -- mysqli_field_count — Returns the number of columns for the most recent query
面向对象风格
过程化风格
$link
)
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.
link
仅以过程化样式:由 mysqli_connect() 或 mysqli_init() 返回的链接标识。
An integer representing the number of fields in a result set.
Example #1 $mysqli->field_count example
面向对象风格
<?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 ( "SELECT * FROM friends" );
if ( $mysqli -> field_count ) {
$result = $mysqli -> store_result ();
$row = $result -> fetch_row ();
$result -> close ();
}
$mysqli -> close ();
?>
过程化风格
<?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 , "SELECT * FROM friends" );
if ( mysqli_field_count ( $link )) {
$result = mysqli_store_result ( $link );
$row = mysqli_fetch_row ( $result );
mysqli_free_result ( $result );
}
mysqli_close ( $link );
?>
[#1] dedlfix [2006-07-18 10:26:29]
There are MYSQLI_TYPE_* constants for the type property (listed in http://php.net/manual/en/ref.mysqli.php).
e.g.
<?php
if ($finfo->type == MYSQLI_TYPE_VAR_STRING)
// a VARCHAR