php - 帮助创建一个可重用的 PHP 函数，它将 'dynamically' 调用其他函数

Question

这是我第一次尝试认真地使用 MySQL 中的关系数据库和使用 CodeIgniter 在 PHP 中创建的某种 CMS。
我来到了必须在几个多对多相关表中插入一些数据的部分。
在我的代码中一切正常(好吧，只需几分钟的测试)，但我需要一些帮助来创建可重用的函数，这将帮助我在我的表中建立所有关系...

我试图在我的代码中注释所有内容，所以所有的解释都在那里...

<?php
function add(){

 // This is what user posted in form.
 // There are two input fields:
 // name is always only one record
 // country can be a single record or array separated with " | " characters
 // I use CodeIgniter's $this->input->post instead of $_POST[]
 $name = $this->input->post('name');
 $countries = $this->input->post('country');

 // Inserting data to first table
 $data = array('firstName' => htmlentities($name)); // preparing array for inserting
 $insert_name = $this->db->insert('names', $data); // inserting with CodeIgniter's help
 $last_inserted_ID = $this->db->insert_id(); // getting last inserted ID

 // Inserting data to second table

 // Formatting of posted string of countries
 // Users can post strings similar to this:
 // "Austria"
 // "Austria |"
 // "Austria | "
 // "Austria | Australia"
 // "Austria | Australia |"
 // "Austria | Australia | "
 // and similar variations
 // What I need here is clear array with country names
 $separator = strpos($countries,"|"); // check for "|" character
 if ($separator === FALSE){ // if there is no "|" character in string
  $countries_array[] = $countries; // array is only one value (only one country)
 } else {
  $countries_array = explode(" | ", $countries); // explode my array
  if (end($countries_array) == ""){ // if last item in array is ""
   array_pop($countries_array); // eliminate last (empty) item
  }
 }

 // Now, this is the part I think I will use lots of times.
 // I would like to make this a separate function so I could use it in many places :)
 // I would pass to that function few values and I would use one of them
 // to call different functions in this same class.
 // I guess I should pass data ($countries_array) and function names I wish to call?????? This is problematic part for my brain :))
 // Check the comments below...
 for ($i = 0; $i < sizeof($countries_array); $i++){
  $insertIDS = array(); // this will be an array of IDs of all countries
  $tempdata = $this->get_countries($countries_array[$i]); // query which looks if there is a country with specific name
                // Right here, instead of calling $this->get_countries
                // I would like to call different functions, for example
                // $this->get_links($links_array[$i])
                // or $this->get_categories($categories_array[$i])
                // etc.
  if(sizeof($tempdata) != 0){ // so, if a record already exists
   foreach ($tempdata as $k => $v){
    $insertIDS[] = $k; // insert those IDs in our array
   }
  } else { // and if a record does not exist in db
   $this->add_country($countries_array[$i]); // add it as a new record...
               // This is also one of the places where I would call different functions
               // for example $this->add_link($links_array[$i])
               // or $this->add_categories($categories_array[$i])
               // etc.
   $insertIDS[] = $this->db->insert_id(); // ...get its ID and add it to array
  }

  // Finally, insert all IDs into junction table!
  foreach ($insertIDS as $idKey => $idValue){
   $this->add_names_countries($last_inserted_ID, $idValue); // Another place for calling different functions
                  // example $this->add_names_links($last_inserted_ID, $idValue)
                  // etc.
  }
 }

}
?>

好吧，现在看这段代码，我发现我可以把格式化部分也放在那个函数中，但现在这不是那么重要......

非常感谢您对此的任何帮助!!

Answer 1

执行此操作的首选方法是使用 Table Data Gateway .而不是

$this->db->insert('countries', $data);

您为数据库中的每个表创建类。每个表都将 CRUD 逻辑封装到类中，例如

class Countries
{
    $protected $_db;

    public function __construct($db)
    {
        $this->_db = $db;
    }

    public function save(array $countries)
    {
        $this->db->insert('countries', $countries);
    }

    // ... other methods
}

此外，我建议使用transactions对于这种工作，因为所有这些东西都属于一起，如果其中一个查询失败，您可能不想插入任何数据。我不知道 CodeIgnitor 如何处理事务，但基本上，您应该这样做:

$this->db->startTransaction();          // like try/catch for databases
$countries = new Countries($this->db);
$countries->save($countryData);
$links = new Links($this->db);
$links->save($linkData);
// ...
if($this->db->commit() === false) {     // returns true when no errors occured
    $this->db->rollback();              // undos in case something went wrong
}

虽然这不能回答您如何动态调用函数的问题(call_user_func() 可以做到这一点)，但按照上面的建议进行操作会使您的代码更易于维护。

您的问题有点含糊，您是想按顺序运行所有功能，还是只想根据用户提交的内容进行交换。对于第一种情况，使用事务方法。对于第二种情况，您只需实例化适当的类并调用保存方法。