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- Mysqli
- mysqli_result
mysqli_result::$field_count
mysqli_num_fields
(PHP 5, PHP 7, PHP 8)
mysqli_result::$field_count -- mysqli_num_fields — Gets the number of fields in the result set
说明
面向对象风格
int $mysqli_result->field_count;过程化风格
mysqli_num_fields(mysqli_result$result): int
Returns the number of fields in the result set.
参数
-
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。
返回值
An int representing the number of fields.
范例
示例 #1 面向对象风格
<?php
mysqli_report(MYSQLI_REPORT_ERROR | MYSQLI_REPORT_STRICT);
$mysqli = new mysqli("localhost", "my_user", "my_password", "world");
$result = $mysqli->query("SELECT Name, CountryCode, District, Population FROM City ORDER BY ID LIMIT 1");
/* Get the number of fields in the result set */
$field_cnt = $result->field_count;
printf("Result set has %d fields.\n", $field_cnt);
示例 #2 过程化风格
<?php
mysqli_report(MYSQLI_REPORT_ERROR | MYSQLI_REPORT_STRICT);
$link = mysqli_connect("localhost", "my_user", "my_password", "world");
$result = mysqli_query($link, "SELECT Name, CountryCode, District, Population FROM City ORDER BY ID LIMIT 1");
/* Get the number of fields in the result set */
$field_cnt = mysqli_num_fields($result);
printf("Result set has %d fields.\n", $field_cnt);
以上例程会输出：
Result set has 4 fields.
参见
- mysqli_fetch_field() - Returns the next field in the result set
User Contributed Notes
There are no user contributed notes for this page.官方地址：https://www.php.net/manual/en/mysqli-result.field-count.php