Call to a member function fetch_row() on a non-object的问题

[zonas1991]

运行出错：Fatal error: Call to a member function fetch_row() on a non-object in E:\AppServ\www\exercitation\Show.php on line 30

<?PHP
$existRecord = False;
$objContent = new Content();
$results = $objContent->load_content_byPage($pageNo, $pageSize);
// 使用while语句显示所有$results中的留言数据
while($row = $results->fetch_row()) { //第30行
$existRecord = True;
?>


最后也有如果没数据输出了。
<?PHP
} // end of while
if(!$existRecord) {
?>
<tr>
<td width="148" height="16" align=center class="main">没有留言数据</td>
</tr>
<?PHP
} // end of if
echo("</table></center></div>");
} // end of function
?>

数据库连接是没问题的。数据也有手动插入了。

[一起混吧]

$results 不是一个资源集，初步怀疑数据库操作类没有传入函数。

[zonas1991]

引用 1 楼 jordan102 的回复:

$results 不是一个资源集，初步怀疑数据库操作类没有传入函数。

不明白，我把数据库操作全贴出来吧

[zonas1991]

<?PHP class Content { var $conn; public $ContId; // 留言ID号，主键 public $Subject; // 留言标题 public $Words; // 留言内容 public $UserName; // 留言人姓名 public $Face; // 脸谱图标文件名 public $Email; // 电子邮件 public $Homepage; // 主页 public $CreateTime; // 创建日期和时间 public $UpperId; // 上级留言ID，如果不是回帖，则UpperId = 0 function __construct() { // 连接数据库 $this->conn = mysqli_connect("localhost", "root", "110120", "book"); mysqli_query($this->conn, "SET NAMES gbk"); } function __destruct() { // 关闭连接 mysqli_close($this->conn); } // 获取留言的内容 function GetInfo($Id) { $sql = "SELECT * FROM Content WHERE ContId=" . $Id; $result = $this->conn->query($sql); if($row = $result->fetch_row()) { $this->ContId = $Id; $this->Subject = $row[1]; $this->Words = $row[2]; $this->UserName = $row[3]; $this->Face = $row[4]; $this->Email = $row[5]; $this->Homepage = $row[6]; $this->CreateTime = $row[7]; $this->UpperId = (int)$row[8]; } } // 返回表Content中的记录总数量 function GetRecordCount() { $sql = "SELECT COUNT(*) FROM Content"; $result = $this->conn->query($sql); if($row = $result->fetch_row()) Return (int)$row[0]; else Return 0; } // 插入新记录 function insert() { $sql = "INSERT INTO Content (Subject, Words, UserName, Face, Email, Homepage, CreateTime, UpperId) VALUES('" . $this->Subject . "', '" . $this->Words . "', '" . $this->UserName . "', '" . $this->Face . "', '" . $this->Email . "', '" . $this->Homepage . "', '" . $this->CreateTime . "', " . $this->UpperId . ")"; $this->conn->query($sql); } // 删除指定的留言记录 function delete($Id) { $sql = "DELETE FROM Content WHERE ContId=" . $Id . " OR UpperId=" . $Id; $this->conn->query($sql); } function load_content_byUpperid($uid) { $sql = "SELECT * FROM Content WHERE UpperId=" . $uid . " ORDER BY CreateTime DESC"; $result = $this->conn->query($sql); Return $result; } function load_content_byPage($pageNo, $pageSize) { $sql = "SELECT * FROM Content ORDER BY CreateTime DESC LIMIT " . ($pageNo-1) * $pageSize . "," . $pageSize; $result = $this->conn->query($sql); Return $result; } } ?>

[ayzen1988]

你这个数据库类是不是少了一个query()函数？ 还是你粘贴少了？

function query($sql)
{
 return mysqli_query($this->con,$sql);
}

[一起混吧]

$result = $this->conn->query($sql) or die($this->conn->error); //改成这样能不能看到错误信息

[zonas1991]

引用 4 楼 jordan102 的回复:

$result = $this->conn->query($sql) or die($this->conn->error); //改成这样能不能看到错误信息

You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '' at line 1

[一起混吧]

echo $sql ;//贴出结果