(PHP 5, PHP 7, PHP 8)
mysqli_result::field_seek -- mysqli_field_seek — Set result pointer to a specified field offset
面向对象风格
$index): bool过程化风格
Sets the field cursor to the given offset. The next call to mysqli_fetch_field() will retrieve the field definition of the column associated with that offset.
注意:
To seek to the beginning of a row, pass an offset value of zero.
result仅以过程化样式：由 mysqli_query()、mysqli_store_result()、 mysqli_use_result()、mysqli_stmt_get_result() 返回的 mysqli_result 对象。
index
The field number. This value must be in the range from
0 to number of fields - 1.
成功时返回 true， 或者在失败时返回 false。
示例 #1 面向对象风格
<?php
$mysqli = new mysqli("localhost", "my_user", "my_password", "world");
/* check connection */
if (mysqli_connect_errno()) {
printf("Connect failed: %s\n", mysqli_connect_error());
exit();
}
$query = "SELECT Name, SurfaceArea from Country ORDER BY Code LIMIT 5";
if ($result = $mysqli->query($query)) {
/* Get field information for 2nd column */
$result->field_seek(1);
$finfo = $result->fetch_field();
printf("Name: %s\n", $finfo->name);
printf("Table: %s\n", $finfo->table);
printf("max. Len: %d\n", $finfo->max_length);
printf("Flags: %d\n", $finfo->flags);
printf("Type: %d\n\n", $finfo->type);
$result->close();
}
/* close connection */
$mysqli->close();
?>
示例 #2 过程化风格
<?php
$link = mysqli_connect("localhost", "my_user", "my_password", "world");
/* check connection */
if (mysqli_connect_errno()) {
printf("Connect failed: %s\n", mysqli_connect_error());
exit();
}
$query = "SELECT Name, SurfaceArea from Country ORDER BY Code LIMIT 5";
if ($result = mysqli_query($link, $query)) {
/* Get field information for 2nd column */
mysqli_field_seek($result, 1);
$finfo = mysqli_fetch_field($result);
printf("Name: %s\n", $finfo->name);
printf("Table: %s\n", $finfo->table);
printf("max. Len: %d\n", $finfo->max_length);
printf("Flags: %d\n", $finfo->flags);
printf("Type: %d\n\n", $finfo->type);
mysqli_free_result($result);
}
/* close connection */
mysqli_close($link);
?>
以上例程会输出：
Name: SurfaceArea Table: Country max. Len: 10 Flags: 32769 Type: 4