mysqli_result::data_seek()

(PHP 5, PHP 7)

Adjusts the result pointer to an arbitrary row in the result

说明

面向对象风格
mysqli_result::data_seek(int $offset): bool

过程化风格
mysqli_data_seek(mysqli_result$result,int $offset): bool

The mysqli_data_seek() function seeks to an arbitrary result pointer specified by the$offsetin the result set.

参数

$result

仅以过程化样式：由mysqli_query()，mysqli_store_result()或mysqli_use_result()返回的结果集标识。

$offset

The field offset. Must be between zero and the total number of rows minus one(0..mysqli_num_rows() 1).

返回值

成功时返回TRUE，或者在失败时返回FALSE。

注释

Note:

This function can only be used with buffered results attained from the use of the mysqli_store_result() or mysqli_query() functions.

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();
}
$query = "SELECT Name, CountryCode FROM City ORDER BY Name";
if ($result = $mysqli->query($query)) {
    /* seek to row no. 400 */
    $result->data_seek(399);
    /* fetch row */
    $row = $result->fetch_row();
    printf ("City: %s  Countrycode: %s\n", $row[0], $row[1]);
    /* free result set*/
    $result->close();
}
/* close connection */
$mysqli->close();
?>

Example #2 过程化风格

<?php
/* Open a connection */
$link = mysqli_connect("localhost", "my_user", "my_password", "world");
/* check connection */
if (!$link) {
    printf("Connect failed: %s\n", mysqli_connect_error());
    exit();
}
$query = "SELECT Name, CountryCode FROM City ORDER BY Name";
if ($result = mysqli_query($link, $query)) {
    /* seek to row no. 400 */
    mysqli_data_seek($result, 399);
    /* fetch row */
    $row = mysqli_fetch_row($result);
    printf ("City: %s  Countrycode: %s\n", $row[0], $row[1]);
    /* free result set*/
    mysqli_free_result($result);
}
/* close connection */
mysqli_close($link);
?>

以上例程会输出：

City: Benin City  Countrycode: NGA

参见

• mysqli_store_result() 转移上一次查询返回的结果集
• mysqli_fetch_row() Get a result row as an enumerated array
• mysqli_fetch_array() Fetch a result row as an associative, a numeric array, or both
• mysqli_fetch_assoc() Fetch a result row as an associative array
• mysqli_fetch_object() Returns the current row of a result set as an object
• mysqli_query() 对数据库执行一次查询
• mysqli_num_rows() Gets the number of rows in a result

This is useful function when you try to loop through the resultset numerous times.
For example:
<?php
$result = mysqli_query($connection_id,$query);
while ($row = mysqli_fetch_assoc($result))
 {
 // Looping through the resultset.
 }
// Now if you need to loop through it again, you would first call the seek function:
mysqli_data_seek($result,0);
while ($row = mysqli_fetch_assoc($result))
 {
 // Looping through the resultset again.
 }
?>