mysqli_stmt::$num_rows
mysqli_stmt::$num_rows
mysqli_stmt_num_rows
(PHP 5, PHP 7)
mysqli_stmt :: $ num_rows - mysqli_stmt_num_rows - 返回语句结果集中的行数
描述
面向对象的风格
int $mysqli_stmt->num_rows;
程序风格
int mysqli_stmt_num_rows ( mysqli_stmt $stmt )
返回结果集中的行数。mysqli_stmt_num_rows（）的使用取决于您是否使用mysqli_stmt_store_result（）来缓冲语句句柄中的整个结果集。
如果使用mysqli_stmt_store_result（），则可以立即调用mysqli_stmt_num_rows（）。
参数
`stmt`
仅过程风格：由mysqli_stmt_init（）返回的语句标识符。
返回值
表示结果集中行数的整数。
Examples
Example #1 Object oriented style
<?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 Procedural style
<?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
?>
上面的例子会输出：
Number of rows: 20.
