PHP 手册
MySQLi_STMT

mysqli_stmt::$num_rows

mysqli_stmt_num_rows

(PHP 5)

mysqli_stmt::$num_rows -- mysqli_stmt_num_rowsReturn the number of rows in statements result set

说明

面向对象风格

过程化风格

int mysqli_stmt_num_rows ( mysqli_stmt $stmt )

Returns the number of rows in the result set. The use of mysqli_stmt_num_rows() depends on whether or not you used mysqli_stmt_store_result() to buffer the entire result set in the statement handle.

If you use mysqli_stmt_store_result(), mysqli_stmt_num_rows() may be called immediately.

参数

stmt

仅以过程化样式:由 mysqli_stmt_init() 返回的 statement 标识。

返回值

An integer representing the number of rows in result set.

范例

Example #1 面向对象风格

<?php
/* Open a connection */
$mysqli = new mysqli("localhost""my_user""my_password""world");

/* check connection */
if (mysqli_connect_errno()) {
    
printf("Connect failed: %s\n"mysqli_connect_error());
    exit();
}

$query "SELECT Name, CountryCode FROM City ORDER BY Name LIMIT 20";
if (
$stmt $mysqli->prepare($query)) {

    
/* execute query */
    
$stmt->execute();

    
/* store result */
    
$stmt->store_result();

    
printf("Number of rows: %d.\n"$stmt->num_rows);

    
/* close statement */
    
$stmt->close();
}

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

Example #2 过程化风格

<?php
/* Open a connection */
$link mysqli_connect("localhost""my_user""my_password""world");

/* check connection */
if (mysqli_connect_errno()) {
    
printf("Connect failed: %s\n"mysqli_connect_error());
    exit();
}

$query "SELECT Name, CountryCode FROM City ORDER BY Name LIMIT 20";
if (
$stmt mysqli_prepare($link$query)) {

    
/* execute query */
    
mysqli_stmt_execute($stmt);

    
/* store result */
    
mysqli_stmt_store_result($stmt);

    
printf("Number of rows: %d.\n"mysqli_stmt_num_rows($stmt));

    
/* close statement */
    
mysqli_stmt_close($stmt);
}

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

以上例程会输出:

Number of rows: 20.

参见


MySQLi_STMT
PHP 手册