我有关于将数据库连接到我的php并获取数据的问题。 错误是警告:
mysqli_query(( 期望参数 1 是 mysqli,给定
空
这是我的 2 个文件类和实现
我的代码:
<?php
class DB{
//this is my protected data
protected $db_hostname = 'localhost';
protected $db_username = 'root';
protected $db_password = '';
protected $db_name = 'blog';
public function connect(){
//connection to DB
$connect_db = mysqli_connect($this->db_hostname, $this->db_username, $this->db_password, $this->db_name) or die(mysqli_connect_error($connect_db));
//close the connection
mysqli_close($connect_db);
//for test
echo "Greate";
}
}
?>
第二个文件:-
$connection = $db->connect();
$result = "SELECT * FROM blog_posts ";
$query = mysqli_query($connection, $result) or die(mysqli_error());
//loop through my data
while($row = mysqli_fetch_array($query)){
?>
<div class="well">
//print data
By: <?php echo $row->author ?>
<p><?php echo $row->title ?></p>
</div>
<?php } ?>
?>
函数需要如下所示:-
public function connect(){
//connection to DB
$connect_db = mysqli_connect($this->db_hostname, $this->db_username, $this->db_password, $this->db_name);
if(mysqli_connect_error()){ // you can use mysqli_connect_errorno() also
die(mysqli_connect_error()); // remove $connect_db
}else{
return $connect_db; // return connection object
}
}
也更改如下:-
while($row = mysqli_fetch_assoc($query)){
?>
<div class="well">
//print data
By: <?php echo $row['author']; ?>
<p><?php echo $row['title']; ?></p>
</div>
<?php } ?>
?>
注意:- mysqli_fetch_array()
将为您提供索引+关联数组。虽然mysqli_fetch_assoc()
只会给你关联数组,这使你的结果数组更轻。谢谢
寻找更好的错误报告:- http://php.net/manual/en/mysqli-driver.report-mode.php