Warning: Creating default object from empty value in D:\phpstudy_pro\WWW\jfdd_v2.0\jfdd\config.php on line 58 No database selected
时间: 2023-08-13 21:04:07 浏览: 106
回答: 这个错误提示表明在D:\phpstudy_pro\WWW\jfdd_v2.0\jfdd\config.php文件的第58行,尝试从一个空值创建默认对象,而没有选择数据库。这可能是因为在连接数据库之前没有选择要使用的数据库。你可以在连接数据库之前使用mysqli_select_db函数来选择数据库。例如,你可以使用以下代码来选择数据库:
```
$db = mysqli_connect("localhost", "username", "password");
if (!$db) {
die("连接数据库失败: " . mysqli_connect_error());
}
// 选择要使用的数据库
mysqli_select_db($db, "database_name");
```
请确保将"username"替换为你的数据库用户名,"password"替换为你的数据库密码,"database_name"替换为你要使用的数据库名称。这样就可以解决"Creating default object from empty value"和"No database selected"的问题了。
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