PHP静态变量问题

好的，这是我正在处理的一个函数。现在请注意，我是编程新手，这可能比我所问的有更多的错误。基本上，如何设置变量：

${"MySQL_Connection_" . $MySQL_Connection}

当我用不同的“模式”调用函数时使用它。我试过使用：

static

但从你们所说的话来看。关于它的用途，我得到了严重的错误信息。以下是我的“真实生活”示例：

---

奇怪的是，我一直在这个网站上回答我自己的问题，这甚至违背了拥有这个网站的意义，但我发现了如何创建和使用更有意义的类。希望有人会说要学习课程，并给出一个班级的例子来做到这一点。但我还是自己想出来了。再次感谢你的帮助。伟大的网站。这里的每个人都很友善，乐于助人。就像在国税局开派对一样

class DB {

/*

// Layout

// $DB1 -> Set_Connection_Pass_Info ("default");
// $DB1 -> Set_Connection_Fail_Info ("default");
// $DB1 -> Connection_Report_Short ();
// $DB1 -> Connection_Report_Long ();
// $DB1 -> Set_Query_Pass_Info ("default");
// $DB1 -> Set_Query_Fail_Info ("default");
// $DB1 -> Query_Report_Short ();
// $DB1 -> Query_Report_Long ();

include "class.php";

$DB1 = new DB;

//  Connection Name - Server Name - User Name - User Password - Database Name: "null" if no Database
$DB1 -> Connect("Connection_1","localhost","root","UserMain1324!","Database_Test_1");

$Connection_1 -> Query (
"Connection_1",
"

"
);

$DB1 -> Close ("Connection_1");
*/

// ****************************************
//          Static Public Variables
// **************************************** 
    static public $MySQL_Connection_ = array();
    //DB::$MySQL_Connection_[$MySQL_Connection] =

    static public $MySQL_Connection_Success_Message = "Connected Successfully or Still Connected";
    //DB::$MySQL_Connection_Success_Message = 

    static public $MySQL_Connection_Failure_Message = "Connection Failed";
    //DB::$MySQL_Connection_Failure_Message = 

    static public $MySQL_Connection_Status_Short = 0;
    //DB::$MySQL_Connection_Status_Short = 

    static public $MySQL_Connection_Status_Long = "!!! MySQL: NOT CONNECTED !!!";
    //DB::$MySQL_Connection_Status_Long =

    static public $MySQL_Commands = "null";
    //DB::$MySQL_Commands = 

    static public $MySQL_Query_Success_Message = "MySQL Query Success";
    //DB::$MySQL_Query_Success_Message = 

    static public $MySQL_Query_Failure_Message = "MySQL Query Failure";
    //DB::$MySQL_Query_Failure_Message = 

    static public $MySQL_Query_Status_Short = 0;
    //DB::$MySQL_Query_Status_Short = 

    static public $MySQL_Query_Status_Long = "!!! CANT QUERY: QUERY EMPTY or NOT CONNECTED !!!";
    //DB::$MySQL_Query_Status_Long = 

// ****************************************
// Function to end connection to a database
// ****************************************
    function Close (
        $MySQL_Connection
    )
    {
        DB::$MySQL_Connection_[$MySQL_Connection] = null;

        // Set
        DB::$MySQL_Connection_Status_Short = 0;
        DB::$MySQL_Connection_Status_Long = "Was Connected: NOW DISCONNECTED !!!";
    } // END Function (MySQL_Close)

// *****************************************************
// Function to set the $MySQL_Connection_Success_Message
// *****************************************************
function Set_Connection_Pass_Info ($Input_Variable){

    switch ($Input_Variable) {
        case "default":
            DB::$MySQL_Connection_Success_Message = "Connected Successfully";
            break;
        default:
            DB::$MySQL_Connection_Success_Message = $Input_Variable;
    }

} // END function Set_MySQL_Connection_Success_Message

// *****************************************************
// Function to set the $MySQL_Connection_Failure_Message
// *****************************************************
function Set_Connection_Fail_Info ($Input_Variable){

    switch ($Input_Variable) {
        case "default":
            DB::$MySQL_Connection_Failure_Message = "Connection Failed";
            break;
        default:
            DB::$MySQL_Connection_Failure_Message = $Input_Variable;
    }

} // END function $MySQL_Connection_Failure_Message

// ************************************
// Function to Print MySQL Status Short
// ************************************
    function Connection_Report_Short ()
    {
        echo DB::$MySQL_Connection_Status_Short . "<br> <br>";
    } // END Function (MySQL_Connection_Status_Report_Short)

// ***********************************
// Function to Print MySQL Status Long
// ***********************************
    function Connection_Report_Long ()
    {
        echo DB::$MySQL_Connection_Status_Long . "<br> <br>";
    } // END Function (MySQL_Connection_Status_Report_Long)

// ****************************************
// Function to create a general MySQL Query
// ****************************************
    function Query (
        $MySQL_Connection,
        // MySQL Query
        $MySQL_Query
    )
    {
        // Create MySQL Query
        // DB::$MySQL_Commands = $MySQL_Query;

        // Create MySQL Query
        try {
            // Prepare statement
            DB::$MySQL_Commands = DB::$MySQL_Connection_[$MySQL_Connection]->prepare($MySQL_Query);

            // execute the query
            DB::$MySQL_Commands->execute();

            // Set 
            DB::$MySQL_Query_Status_Short = 1;
            DB::$MySQL_Query_Status_Long = DB::$MySQL_Query_Success_Message;


            // echo a message to say the UPDATE succeeded
            // echo DB::$MySQL_Commands->rowCount() . " records UPDATED successfully";
            }

        // MySQL Query Error Handling
        catch (PDOException $PDOException_Error)
            {
            // Set
            DB::$MySQL_Query_Status_Short = 0;
            DB::$MySQL_Query_Status_Long = DB::$MySQL_Query_Failure_Message . ": " . $MySQL_Query . "<br>" . $PDOException_Error->getMessage();
            }

    } // END Function (MySQL_Query)

// *************************************************
// Function to set the $MySQL_Query_Success_Message;
// *************************************************
function Set_Query_Pass_Info ($Input_Variable){

    switch ($Input_Variable) {
        case "default":
            DB::$MySQL_Query_Success_Message = "MySQL Query Success";
            break;
        default:
            DB::$MySQL_Query_Success_Message = $Input_Variable;
    }

} // END function Set_MySQL_Connection_Success_Message

// *************************************************
// Function to set the $MySQL_Query_Failure_Message;
// *************************************************
function Set_Query_Fail_Info ($Input_Variable){

    switch ($Input_Variable) {
        case "default":
            DB::$MySQL_Query_Failure_Message = "MySQL Query Failure";
            break;
        default:
            DB::$MySQL_Query_Failure_Message = $Input_Variable;
    }

} // END function $MySQL_Connection_Failure_Message

// ******************************************
// Function to Print MySQL Query Status Short
// ******************************************
    function Query_Report_Short ()
    {
        echo DB::$MySQL_Query_Status_Short . "<br> <br>";
    } // END Function (MySQL_Query_Status_Report_Long)

// *****************************************
// Function to Print MySQL Query Status Long
// *****************************************
    function Query_Report_Long ()
    {
        echo DB::$MySQL_Query_Status_Long . "<br> <br>";
    } // END Function (MySQL_Query_Status_Report_Long)

// Main function //

// ****************************
// Function to connect to MySQL
// ****************************
    function Connect(
        $MySQL_Connection,
        $Database_Server_Name,
        $Database_Server_Username,
        $Database_Server_Username_Password,
        $Database_Name // Set to "null" if not connecting to a database
    )
    {
        // Create Connection
        try {
            // Add database portion of cononect statement if connecting to a database
            if($Database_Name = "null"){
                $Database_Connection_Addon = "";
            } else {
                $Database_Connection_Addon = ";dbname=$Database_Name";
            }

            // Create Connection
            DB::$MySQL_Connection_[$MySQL_Connection] = new PDO("mysql:host=$Database_Server_Name" . "$Database_Connection_Addon", $Database_Server_Username, $Database_Server_Username_Password);

            // Connection Attributes
            DB::$MySQL_Connection_[$MySQL_Connection]->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

            // Set
            DB::$MySQL_Connection_Status_Short = 1;
            DB::$MySQL_Connection_Status_Long =  DB::$MySQL_Connection_Success_Message;

            }

        // Connection Error Handling
        catch (PDOException $PDOException_Error)
            {
            // Set
            DB::$MySQL_Connection_Status_Short = 0;
            DB::$MySQL_Connection_Status_Long = DB::$MySQL_Connection_Failure_Message . ": " . $PDOException_Error->getMessage();
            }

    } // END Function (MySQL_Connect)   

} // END CLASS (DB)

classdb{
/*
//布局
//$DB1->Set_Connection_Pass_Info（“默认”）；
//$DB1->设置连接失败信息（“默认”）；
//$DB1->Connection_Report_Short（）；
//$DB1->Connection_Report_Long（）；
//$DB1->Set_Query_Pass_Info（“默认”）；
//$DB1->设置查询失败信息（“默认”）；
//$DB1->Query_Report_Short（）；
//$DB1->Query_Report_Long（）；
包括“class.php”；
$DB1=新数据库；
//连接名称-服务器名称-用户名-用户密码-数据库名称：如果没有数据库，则为“null”
$DB1->Connect（“Connection_1”、“localhost”、“root”、“UserMain1324！”、“Database_Test_1”）；
$Connection\u 1->Query(
“连接1”，
"
"
);
$DB1->关闭（“连接1”）；
*/
// ****************************************
//静态公共变量
// **************************************** 
静态公共$MySQL\u连接\uu=array（）；
//DB:：$MySQL\u连接\[$MySQL\u连接]=
静态公共$MySQL\u Connection\u Success\u Message=“已成功连接或仍在连接”；
//DB:：$MySQL\u连接\u成功\u消息=
静态公共$MySQL\u连接\u失败\u消息=“连接失败”；
//DB:：$MySQL\u连接\u失败\u消息=
静态公共$MySQL\u连接\u状态\u短=0；
//DB:：$MySQL\u连接\u状态\u短=
静态公共$MySQL\u Connection\u Status\u Long=“！！！MySQL:未连接！！！”；
//DB:：$MySQL\u连接\u状态\u长=
静态公共$MySQL\u命令=“null”；
//DB:：$MySQL_命令=
静态公共$MySQL\u Query\u Success\u Message=“MySQL Query Success”；
//DB:：$MySQL\u查询\u成功\u消息=
静态公共$MySQL\u Query\u Failure\u Message=“MySQL Query Failure”；
//DB:：$MySQL\u查询\u失败\u消息=
静态public$MySQL\u Query\u Status\u Short=0；
//DB:：$MySQL\u查询\u状态\u短=
静态公共$MySQL\u Query\u Status\u Long=“！！！无法查询：查询为空或未连接！！！”；
//DB:：$MySQL\u查询\u状态\u长=
// ****************************************
//函数结束与数据库的连接
// ****************************************
功能关闭(
$MySQL\u连接
)
{
DB:：$MySQL\u Connection\u[$MySQL\u Connection]=null；
//设置
DB:：$MySQL\u Connection\u Status\u Short=0；
DB:：$MySQL\u Connection\u Status\u Long=“已连接：现在已断开！！！”；
}//结束函数（MySQL\u Close）
// *****************************************************
//函数设置$MySQL\u Connection\u Success\u消息
// *****************************************************
函数集\连接\传递\信息（$Input\变量）{
开关（$Input_变量）{
案例“默认”：
DB:：$MySQL\u Connection\u Success\u Message=“Connected Successfully”；
打破
违约：
DB:：$MySQL\连接\成功\消息=$Input\变量；
}
}//结束函数集\u MySQL\u连接\u成功\u消息
// *****************************************************
//函数设置$MySQL\u连接\u失败\u消息
// *****************************************************
函数集\连接\失败\信息（$Input\变量）{
开关（$Input_变量）{
案例“默认”：
DB:：$MySQL\u Connection\u Failure\u Message=“Connection Failed”；
打破
违约：
DB:：$MySQL\连接\失败\消息=$Input\变量；
}
}//结束函数$MySQL\u连接\u失败\u消息
// ************************************
//用于打印MySQL状态的函数
// ************************************
功能连接\u报告\u短（）
{
echo数据库：：$MySQL\u连接\u状态\u短。“

”；
}//结束函数（MySQL\u连接\u状态\u报告\u短）
// ***********************************
//函数以长时间打印MySQL状态
// ***********************************
函数连接报告长（）
{
echo DB:：$MySQL\u连接\u状态\u长。“

”；
}//结束函数（MySQL\u连接\u状态\u报告\u长）
// ****************************************
//函数创建一个通用的MySQL查询
// ****************************************
函数查询(
$MySQL\u连接，
//MySQL查询
$MySQL\u查询
)
{
//创建MySQL查询
//DB:：$MySQL\u命令=$MySQL\u查询；
//创建MySQL查询
试一试{
//准备报表
DB:$MySQL\u Commands=DB:$MySQL\u Connection\u[$MySQL\u Connection]->prepare（$MySQL\u Query）；
//执行查询
DB:：$MySQL_命令->执行（）；
//设置
DB:：$MySQL\u Query\u Status\u Short=1；
DB:$MySQL\u Query\u Status\u Long=DB:$MySQL\u Query\u Success\u消息；
//回显一条消息，表示更新成功
//echo DB:：$MySQL_命令->行计数（）“记录更新成功”；
}
//MySQL查询错误处理
捕获（PDOException$PDOException_错误）
{
//设置
DB:：$MySQL\u Query\u Status\u Short=0；
DB:$MySQL\u Query\u Status\u Long=DB:$MySQL\u Query\u Failure\u Message.：“：”$MySQL\u Query
class DB {

/*

// Layout

// $DB1 -> Set_Connection_Pass_Info ("default");
// $DB1 -> Set_Connection_Fail_Info ("default");
// $DB1 -> Connection_Report_Short ();
// $DB1 -> Connection_Report_Long ();
// $DB1 -> Set_Query_Pass_Info ("default");
// $DB1 -> Set_Query_Fail_Info ("default");
// $DB1 -> Query_Report_Short ();
// $DB1 -> Query_Report_Long ();

include "class.php";

$DB1 = new DB;

//  Connection Name - Server Name - User Name - User Password - Database Name: "null" if no Database
$DB1 -> Connect("Connection_1","localhost","root","UserMain1324!","Database_Test_1");

$Connection_1 -> Query (
"Connection_1",
"

"
);

$DB1 -> Close ("Connection_1");
*/

// ****************************************
//          Static Public Variables
// **************************************** 
    static public $MySQL_Connection_ = array();
    //DB::$MySQL_Connection_[$MySQL_Connection] =

    static public $MySQL_Connection_Success_Message = "Connected Successfully or Still Connected";
    //DB::$MySQL_Connection_Success_Message = 

    static public $MySQL_Connection_Failure_Message = "Connection Failed";
    //DB::$MySQL_Connection_Failure_Message = 

    static public $MySQL_Connection_Status_Short = 0;
    //DB::$MySQL_Connection_Status_Short = 

    static public $MySQL_Connection_Status_Long = "!!! MySQL: NOT CONNECTED !!!";
    //DB::$MySQL_Connection_Status_Long =

    static public $MySQL_Commands = "null";
    //DB::$MySQL_Commands = 

    static public $MySQL_Query_Success_Message = "MySQL Query Success";
    //DB::$MySQL_Query_Success_Message = 

    static public $MySQL_Query_Failure_Message = "MySQL Query Failure";
    //DB::$MySQL_Query_Failure_Message = 

    static public $MySQL_Query_Status_Short = 0;
    //DB::$MySQL_Query_Status_Short = 

    static public $MySQL_Query_Status_Long = "!!! CANT QUERY: QUERY EMPTY or NOT CONNECTED !!!";
    //DB::$MySQL_Query_Status_Long = 

// ****************************************
// Function to end connection to a database
// ****************************************
    function Close (
        $MySQL_Connection
    )
    {
        DB::$MySQL_Connection_[$MySQL_Connection] = null;

        // Set
        DB::$MySQL_Connection_Status_Short = 0;
        DB::$MySQL_Connection_Status_Long = "Was Connected: NOW DISCONNECTED !!!";
    } // END Function (MySQL_Close)

// *****************************************************
// Function to set the $MySQL_Connection_Success_Message
// *****************************************************
function Set_Connection_Pass_Info ($Input_Variable){

    switch ($Input_Variable) {
        case "default":
            DB::$MySQL_Connection_Success_Message = "Connected Successfully";
            break;
        default:
            DB::$MySQL_Connection_Success_Message = $Input_Variable;
    }

} // END function Set_MySQL_Connection_Success_Message

// *****************************************************
// Function to set the $MySQL_Connection_Failure_Message
// *****************************************************
function Set_Connection_Fail_Info ($Input_Variable){

    switch ($Input_Variable) {
        case "default":
            DB::$MySQL_Connection_Failure_Message = "Connection Failed";
            break;
        default:
            DB::$MySQL_Connection_Failure_Message = $Input_Variable;
    }

} // END function $MySQL_Connection_Failure_Message

// ************************************
// Function to Print MySQL Status Short
// ************************************
    function Connection_Report_Short ()
    {
        echo DB::$MySQL_Connection_Status_Short . "<br> <br>";
    } // END Function (MySQL_Connection_Status_Report_Short)

// ***********************************
// Function to Print MySQL Status Long
// ***********************************
    function Connection_Report_Long ()
    {
        echo DB::$MySQL_Connection_Status_Long . "<br> <br>";
    } // END Function (MySQL_Connection_Status_Report_Long)

// ****************************************
// Function to create a general MySQL Query
// ****************************************
    function Query (
        $MySQL_Connection,
        // MySQL Query
        $MySQL_Query
    )
    {
        // Create MySQL Query
        // DB::$MySQL_Commands = $MySQL_Query;

        // Create MySQL Query
        try {
            // Prepare statement
            DB::$MySQL_Commands = DB::$MySQL_Connection_[$MySQL_Connection]->prepare($MySQL_Query);

            // execute the query
            DB::$MySQL_Commands->execute();

            // Set 
            DB::$MySQL_Query_Status_Short = 1;
            DB::$MySQL_Query_Status_Long = DB::$MySQL_Query_Success_Message;


            // echo a message to say the UPDATE succeeded
            // echo DB::$MySQL_Commands->rowCount() . " records UPDATED successfully";
            }

        // MySQL Query Error Handling
        catch (PDOException $PDOException_Error)
            {
            // Set
            DB::$MySQL_Query_Status_Short = 0;
            DB::$MySQL_Query_Status_Long = DB::$MySQL_Query_Failure_Message . ": " . $MySQL_Query . "<br>" . $PDOException_Error->getMessage();
            }

    } // END Function (MySQL_Query)

// *************************************************
// Function to set the $MySQL_Query_Success_Message;
// *************************************************
function Set_Query_Pass_Info ($Input_Variable){

    switch ($Input_Variable) {
        case "default":
            DB::$MySQL_Query_Success_Message = "MySQL Query Success";
            break;
        default:
            DB::$MySQL_Query_Success_Message = $Input_Variable;
    }

} // END function Set_MySQL_Connection_Success_Message

// *************************************************
// Function to set the $MySQL_Query_Failure_Message;
// *************************************************
function Set_Query_Fail_Info ($Input_Variable){

    switch ($Input_Variable) {
        case "default":
            DB::$MySQL_Query_Failure_Message = "MySQL Query Failure";
            break;
        default:
            DB::$MySQL_Query_Failure_Message = $Input_Variable;
    }

} // END function $MySQL_Connection_Failure_Message

// ******************************************
// Function to Print MySQL Query Status Short
// ******************************************
    function Query_Report_Short ()
    {
        echo DB::$MySQL_Query_Status_Short . "<br> <br>";
    } // END Function (MySQL_Query_Status_Report_Long)

// *****************************************
// Function to Print MySQL Query Status Long
// *****************************************
    function Query_Report_Long ()
    {
        echo DB::$MySQL_Query_Status_Long . "<br> <br>";
    } // END Function (MySQL_Query_Status_Report_Long)

// Main function //

// ****************************
// Function to connect to MySQL
// ****************************
    function Connect(
        $MySQL_Connection,
        $Database_Server_Name,
        $Database_Server_Username,
        $Database_Server_Username_Password,
        $Database_Name // Set to "null" if not connecting to a database
    )
    {
        // Create Connection
        try {
            // Add database portion of cononect statement if connecting to a database
            if($Database_Name = "null"){
                $Database_Connection_Addon = "";
            } else {
                $Database_Connection_Addon = ";dbname=$Database_Name";
            }

            // Create Connection
            DB::$MySQL_Connection_[$MySQL_Connection] = new PDO("mysql:host=$Database_Server_Name" . "$Database_Connection_Addon", $Database_Server_Username, $Database_Server_Username_Password);

            // Connection Attributes
            DB::$MySQL_Connection_[$MySQL_Connection]->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

            // Set
            DB::$MySQL_Connection_Status_Short = 1;
            DB::$MySQL_Connection_Status_Long =  DB::$MySQL_Connection_Success_Message;

            }

        // Connection Error Handling
        catch (PDOException $PDOException_Error)
            {
            // Set
            DB::$MySQL_Connection_Status_Short = 0;
            DB::$MySQL_Connection_Status_Long = DB::$MySQL_Connection_Failure_Message . ": " . $PDOException_Error->getMessage();
            }

    } // END Function (MySQL_Connect)   

} // END CLASS (DB)