Php 如何检测MySQL数据库是否正在运行？

我正在使用XAMPP，我想检测MySQL数据库是否正在运行。我的代码如下所示：

$this->connection = mysqli_connect(
        $this->host,
        $this->name,
        $this->pass,
        $this->db
);

if ($this->connection->connect_errno)
{
        $this->connection = false;
        return false;
} else { $this->connection->set_charset('utf-8'); }

我收到以下日志：

PHP警告：mysqli_connect（）：（HY000/2002）：连接被拒绝

PHP注意：试图在//中获取非对象的属性，这指的是$This->connection->connect\u errno

PHP致命错误：调用布尔值上的成员函数set_charset（）

---

我怎样才能防止这种情况？如何检查数据库是否可用？

首先，您需要为

mysqli\u connect

调用禁用或抑制警告报告，或者将其嵌入

try/catch

块中

然后，不要检查

connect\u errno

，而是首先验证

connection

是否为真实值。像这样

$this->connection = false;
try {
    $this->connection = mysqli_connect(
            $this->host,
            $this->name,
            $this->pass,
            $this->db
    );
    if (!$this->connection || $this->connection->connect_errno)
    {
        $this->connection = false;
        return false;
    } else { 
        $this->connection->set_charset('utf-8'); 
    }
} catch ($e) { //something bad happened. Probably not recoverable.
    $this->connection = false;
    return false;
}

$this->connection = @mysqli_connect( //<-- warnings suppressed
        $this->host,
        $this->name,
        $this->pass,
        $this->db
);

if (!$this->connection || $this->connection->connect_errno) //lazy evaluation will prevent any issues here
{
        $this->connection = false;
        return false;
} else { $this->connection->set_charset('utf-8'); }

---

首先，您需要为

mysqli\u connect

调用禁用或抑制警告报告，或者将其嵌入

try/catch

块中

然后，不要检查

connect\u errno

，而是首先验证

connection

是否为真实值。像这样

$this->connection = false;
try {
    $this->connection = mysqli_connect(
            $this->host,
            $this->name,
            $this->pass,
            $this->db
    );
    if (!$this->connection || $this->connection->connect_errno)
    {
        $this->connection = false;
        return false;
    } else { 
        $this->connection->set_charset('utf-8'); 
    }
} catch ($e) { //something bad happened. Probably not recoverable.
    $this->connection = false;
    return false;
}

$this->connection = @mysqli_connect( //<-- warnings suppressed
        $this->host,
        $this->name,
        $this->pass,
        $this->db
);

if (!$this->connection || $this->connection->connect_errno) //lazy evaluation will prevent any issues here
{
        $this->connection = false;
        return false;
} else { $this->connection->set_charset('utf-8'); }

我不是这个答案的作者，它只是另一篇文章的原始版本，这是给定条件下唯一正确的解决方案

---

首先，您需要为

mysqli\u connect

调用禁用警告报告或抑制它们

然后，不要检查

connect\u errno

，而是首先验证

connection

是否为真实值。像这样

$this->connection = false;
try {
    $this->connection = mysqli_connect(
            $this->host,
            $this->name,
            $this->pass,
            $this->db
    );
    if (!$this->connection || $this->connection->connect_errno)
    {
        $this->connection = false;
        return false;
    } else { 
        $this->connection->set_charset('utf-8'); 
    }
} catch ($e) { //something bad happened. Probably not recoverable.
    $this->connection = false;
    return false;
}

$this->connection = @mysqli_connect( //<-- warnings suppressed
        $this->host,
        $this->name,
        $this->pass,
        $this->db
);

if (!$this->connection || $this->connection->connect_errno) //lazy evaluation will prevent any issues here
{
        $this->connection = false;
        return false;
} else { $this->connection->set_charset('utf-8'); }

$this->connection=@mysqli\u connect（//主机，
$this->name，
$this->pass，
$this->db
);
如果（！$this->connection | |$this->connection->connect\u errno）//延迟求值将防止出现任何问题
{
$this->connection=false；
返回false；
}else{$this->connection->set_字符集（'utf-8'）；}

我不是这个答案的作者，它只是另一篇文章的原始版本，这是给定条件下唯一正确的解决方案

---

首先，您需要为

mysqli\u connect

调用禁用警告报告或抑制它们

然后，不要检查

connect\u errno

，而是首先验证

connection

是否为真实值。像这样

$this->connection = false;
try {
    $this->connection = mysqli_connect(
            $this->host,
            $this->name,
            $this->pass,
            $this->db
    );
    if (!$this->connection || $this->connection->connect_errno)
    {
        $this->connection = false;
        return false;
    } else { 
        $this->connection->set_charset('utf-8'); 
    }
} catch ($e) { //something bad happened. Probably not recoverable.
    $this->connection = false;
    return false;
}

$this->connection = @mysqli_connect( //<-- warnings suppressed
        $this->host,
        $this->name,
        $this->pass,
        $this->db
);

if (!$this->connection || $this->connection->connect_errno) //lazy evaluation will prevent any issues here
{
        $this->connection = false;
        return false;
} else { $this->connection->set_charset('utf-8'); }

$this->connection=@mysqli\u connect（//主机，
$this->name，
$this->pass，
$this->db
);
如果（！$this->connection | |$this->connection->connect\u errno）//延迟求值将防止出现任何问题
{
$this->connection=false；
返回false；
}else{$this->connection->set_字符集（'utf-8'）；}

永远不要抑制警告，这是一个糟糕的计划。我会将连接放在一个

try/catch

中，以便更恰当地处理错误。啊，我不知道警告实际上是可以正确捕获的。谢谢你的提示。我已经改进了我的答案。这是你的答案，你可以随意编辑（只要你没有破坏它）。如果这导致了一场回滚战，请标记为mod help.Meta post关于这个答案的编辑：（cc@YourCommonSense）永远不要抑制警告，这是一个糟糕的计划。我会将连接放在一个

try/catch

中，以便更恰当地处理错误。啊，我不知道警告实际上是可以正确捕获的。谢谢你的提示。我已经改进了我的答案。这是你的答案，你可以随意编辑（只要你没有破坏它）。如果这导致了一场回滚战，那么就标记为mod help.Meta发布关于这个答案的编辑：（cc@YourCommonSense）在

try/catch

语句中执行连接，以便您可以优雅地处理错误。您可以显示整个类吗？在

try/catch

语句中执行连接，以便您可以优雅地处理错误。您可以显示整个类吗？