请参阅下面的编辑

我正在尝试深入研究 PHP 中的 OOP 开发，但我真的开始感到头痛或溃疡。我只是无法理解它，有些部分对我来说太不合逻辑了，而且我不知道从哪里开始，这真的让我很沮丧，因为我相信尝试学习它是值得的，它为我提供了更好的概述关于我的代码。

<罢工>

昨天在网上找了一整天的实例和讲解文章，现在感觉越发的摸不着头脑了。我需要一些实用的技巧，而不是像

class person {
     var $name;
     function set_name($new_name) {
          $this->name = $new_name;
     }
     function get_name() {
          return $this->name;
     }
}
$stefan = new person();
$jimmy = new person;<p></p>

<p>$stefan->set_name("Stefan");
$jimmy->set_name("Jimmy");</p>

<p>echo "Stefan's full name: " . $stefan->get_name();
echo "Jimmy's full name: " . $jimmy->get_name(); </p>

$name = "Stefan"; 
echo "Stefan's full name: ".$name;

class Database{}
class Content extends Database{}
     function showMenu(){}
     function showContent{}
class Clients extends Database{}
     function showClientList{}
     function showClientDetails{}
class Media extends Database{}

class Content extends Database {
    public function topMenu($page){
        $db = new Database();
        $db->connect();
        $db->query("SELECT m_link, m_title, m_accesskey FROM menu WHERE m_type = 'top'"); 
        $res = $db->getResult();
        foreach($res AS $show){
            if($page == $show['m_link']){
                echo("<li id="active">$show['m_title']."</li>\n");
            }else{
                echo("<li>$show['m_title']."</li>\n");
            }
        }
    }
}

$query = "
    SELECT cl.c_id, cl.c_client, cl.c_client_desc, ncc.clco_cl_id, ncc.clco_co_id, co.c_content, ncm.clme_me_id, ncm.clme_cl_id, GROUP_CONCAT(me.m_link) AS images_link
    FROM clienten AS cl
    LEFT JOIN norm_cl_co_rel AS ncc ON cl.c_id = ncc.clco_cl_id
    LEFT JOIN content AS co ON ncc.clco_co_id = co.c_id
    LEFT JOIN norm_cl_me_rel AS ncm ON cl.c_id = ncm.clme_cl_id
    LEFT JOIN media AS me ON me.m_id = ncm.clme_me_id
    WHERE cl.c_client = '".mysql_real_escape_string($_aGET[1])."'
    AND cl.c_language_id = '"._LANGUAGE."' 
    AND cl.c_active = '1'
";

或者我的“故事”看起来像这样:“伙计，放下它并坚持使用过程编码”？

编辑:

好的，在 Fluffeh 的帖子之后，我使用了他的示例并对其进行了一些修改以对其进行测试。问题是我确实得到了一些输出，但不是我想要的。我的输出如下所示

ID: CompanyName
C
Desc: C
Media:
: 
: 
: 
: 
:

while i should get (values are in the database):

ID: CompanyName
CompanyName
Desc: CompanyName is a company
Media:
: Image 1
: Image 2
: Image 3
: Image 4
: Image 5

My code looks like so:

class media{
    public $type;
    public $title;
    public $image;
    public $desc;
}

class client{
    public $name;
    public $desc;
}

class clientDetails{

    private $clientID;
    public $clientName;
    public $clientDesc;
    public $clientMedia = array();
    public $clientMediaFiles = 0;

    public function __construct($myID){
        $this->clientID = $myID;
    }

    public function getMyDetails(){

        $db = new Database();
        $db->connect();
        $db->query("
            SELECT c_client, c_client_desc 
            FROM clienten 
            WHERE c_client = '".mysql_real_escape_string($this->clientID)."'
        ");
        foreach($db->getResult() as $client){
            $this->name = $client['c_client'];
            $this->desc = $client['c_client_desc'];
        }

        $db = new Database();
        $db->connect();
        $db->query("
            SELECT ncm.clme_me_id, ncm.clme_cl_id, cl.c_id, me.m_id, me.m_type, me.m_title, me.m_desc, me.m_link
            FROM norm_cl_me_rel AS ncm
            LEFT JOIN clienten AS cl ON cl.c_id = ncm.clme_cl_id
            LEFT JOIN media AS me ON me.m_id = ncm.clme_me_id
            WHERE me.m_id IN(1,2,3,4,5)
        ");
        foreach($db->getResult() as $media){
            $this->clientMedia[$i]= new media();
            $this->clientMedia[$i]->type = $media['m_type'];
            $this->clientMedia[$i]->title = $media['m_title'];
            $this->clientMedia[$i]->image = $media['m_image'];
            $this->clientMedia[$i]->desc = $media['m_desc'];
            $this->clientMediaFiles++;
        }
    }

    public function displayMyResults(){
        echo "ID: $this->clientID";
        echo "<div><h3>".$this->name."</h3>";
        echo "Desc: ".$this->desc."<br>";
        echo "Media:<br>";
        for($i=0;$i<$this->clientMediaFiles;$i++){
            echo $this->clientMedia[$i]->title." : ".$this->clientMedia[$i]->desc."&lt;br>";
        }
        echo "&lt;/div>";
    }

}

最佳答案

继续使用 OOP。一旦你得到它，你将永远不想回到讨厌的、麻烦的、令人讨厌的、可怕的、疯狂的程序代码。

举个例子:假设我想显示客户的详细信息，因此我需要所有三个表的记录，所以通常我会使用几个连接，就像这样...

这是一个很好的例子，可以用来向您展示 OOP 的用途。

为 ClientDetails 创建一个类

• 在其中创建一个接受 clientID 作为参数的构造函数。
• 在此构造函数中，让它运行代码并使用查询返回的数据填充它的内部变量。
• 创建一个函数，以良好的格式输出返回的数据。
• 现在从您的主要代码创建它并让它显示它的详细信息

突然你一个类只有几行代码，但是2行代码就可以完美展示你的数据。

我将很快添加一些示例代码，看看我是否可以翻找我的一些类来进行演示。

编辑:该死，没有翻阅旧类，对于这个来说太详细了，但我写了一些代码作为示例:

<?php

class clientContact
{
    public $name;
    public $phone;
}

class clientDetails
{
    private $clientID;      //only this class can access this variable.
    public $clientName;     // Anything can change these.
    public $clientPhone;
    public $additionalContacts= array();
    public $associates=0;

    public function __construct($myID)
    // This is a magic function that is called every time we make a new object of this class.
    {
        $this->$clientID=$myID;
    }

    public function getMyDetails()
    // This function will query the database to get it's information properly
    // and populate itself with everything it needs. You could do this as part
    // of the __construct() call, but I didn't want to do TOO much code.
    {
        $sql="select clientName, clientPhone from clients where clientID=".$this->clientID.";";
        // skipping over full SQl bits...
        foreach($stmt as $clientContact)
        {
            $this->clientName=$clientContact->clientName;
            $this->clientPhone=$clientContact->clientPhone;
        }

        $sql="select clientName, clientPhone from associates where assocID=".$this->clientID.";";
        // skipping over full SQl bits...
        foreach($stmt as $clientContact)
        {
            $this->additionalContacts[$i]= new clientContact();
            $this->additionalContacts[$i]->name=$clientContact->name;
            $this->additionalContacts[$i]->phone=$clientContact->phone;
            $this->associates++;
        }

    }

    public function displayMyResults()
    // This function will simply display everything it has in a nicely format
    {
        echo "<div><h3>".$this->clientName."</h3>";
        echo "My contact phone number is :".$this->phone."<br>";
        echo "My associates are:<br>";
        for($i=0;$i<$this-associates;$i++)
        {
            echo $this->additionalContacts[$i]->name." : ".$this->additionalContacts[$i]->phone."<br>";
        }
        echo "</div>";

    }
}

?>

天哪，这又长又可怕对吧？

不是真的。原因如下。

当然，类中有一些代码，但是现在，您可以在主页上执行以下操作:

<?php 

    $someArray=array(36, 25, 76); 
    // This could be from a query, or a form, or anything else

    for($i=0;$i<count($someArray);$i++)
    {
        $currentContact= new clientDetails($someArray[$i]);
        // This is how we create the object.

        $currentContact->getMyDetails();
        // This now tells the object to get it's own data

        $currentContact->displayMyResults();
        // This now displays the data in the object to the page.
        echo "<hr>";
        unset($currentContact);
    }
?>

通过这个 TINY 代码片段，您刚刚显示了所有联系人，并根据需要设置了格式，并且完全按照您想要的方式完美地显示了所有联系人。

现在想象一下，您将这些类型的对象用于所有内容，而不是像这样的一个小例子。论坛上的帖子？一个对象。业务 KPI 的复杂计算？一个对象可以获取它拥有的所有数据，然后计算一个预测，将结果显示在图表中并将其通过电子邮件发送给需要它的用户。

如果您的背景是从上到下执行的 HTML 和 PHP 脚本，OOP 的学习曲线可能会很陡峭，但是当您开始掌握它时，您会希望自己从一开始就学会了它。

编辑:

您的查询中似乎没有 m_image 列:

    $db = new Database();
    $db->connect();
    $db->query("
        SELECT cl.c_id, ncm.clme_me_id, ncm.clme_cl_id, me.m_type, me.m_title, me.m_desc, me.m_link, m_image
        FROM clienten AS cl
        LEFT JOIN norm_cl_me_rel AS ncm ON cl.c_id = ncm.clme_cl_id
        LEFT JOIN media AS me ON me.m_id = ncm.clme_me_id
        WHERE me.m_id IN(1,2,3,4,5)
    ");
    foreach($db->getResult() as $media){
        $this->clientMedia[$i]= new media();
        $this->clientMedia[$i]->type = $media['m_type'];
        $this->clientMedia[$i]->title = $media['m_title'];
        $this->clientMedia[$i]->image = $media['m_image'];
        $this->clientMedia[$i]->desc = $media['m_desc'];
        $this->clientMediaFiles++;
    }

编辑 2:我不是 100% 确定，但可能是返回的字段名称。尝试用这个替换查询:

SELECT cl.c_id as c_id, ncm.clme_me_id as clme_me_id, ncm.clme_cl_id as clme_cl_id, me.m_type as m_type, me.m_title as m_title, me.m_desc as m_desc, me. as m_link
FROM clienten AS cl
LEFT JOIN norm_cl_me_rel AS ncm ON cl.c_id = ncm.clme_cl_id
LEFT JOIN media AS me ON me.m_id = ncm.clme_me_id
WHERE me.m_id IN(1,2,3,4,5)

关于PHP OOP 方法困难，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/11755832/