php - 函数删除测试

Question

全局变量级别范围，我正在尝试实现一个删除功能，并在删除查询中用一个全局变量替换表名，如下面的代码，但是当我在用户单击“删除”之前进行测试时，它已定义，但是当点击按钮后，变量是未定义的。

$GLOBALS['$table'] 由用户在不同的函数中填写，当我回显 $GLOBALS['$table'] 首先，它向我展示了值(value)，这很好。

<?php

function DeleteOption()
{
    include ('../CIEcon.php');

    echo "<form action= 'Delete.php'  method = 'post'>";
    echo $GLOBALS['$table'];
    if (isset($_POST['delete'])) {
        if (empty($_POST['Id']) || $_POST['Id'] == 0) {
            echo "<h4>  please choose something to delete   </h4>";
            echo $GLOBALS['$table'] . "hmmmm";
        }
        else {
            $impid = implode("' , '", $_POST['Id']);
            $sqlDelete = "DELETE " . $GLOBALS['$table'] . " WHERE Id IN ('" . $impid . "')";
            $DeleteQuery = mysqli_query($dbCIE, $sqlDelete) or die("Error : " . mysqli_error($dbCIE));
        }
    } // end of delete...
    else {
        echo "";
    }

    echo "</form >";
}; // End of Delete Function..

这就是用户定义 $Globle['table'] 的方式

<?php
include('../CIEcon.php');

$GLOBALS['$table']="";




function DisplayOption(){
    include('../CIEcon.php');

echo '
            <form action= "Delete.php"  method = "post">
            <table width ="40%" cellpadding ="4" border="1" align="center" >

            <tr >
            <th style ="color: white; background-color: #f26822 ; " >     Select a Catagory To Delete From   </th>

            </tr>';

                echo "<tr>



             <td>". 

            "<select name = lists >
              <option name= nothing value= 0 selected >Choose a Catagory</option>
              <option name= nothing value= 1 >    Advertising     </option>
              <option name= nothing value= 2>    Fiscal          </option>
              <option name= nothing value= 3>    Food            </option>
              <option name= nothing value= 4>    Shopping        </option>
              <option name= nothing value= 5>    Rentals         </option>
              <option name= nothing value= 6>   Setting up       </option>
              <option name= nothing value= 7>    Performances    </option>
              <option name= nothing value= 8>  Registration/Ushering  </option>
              <option name= nothing value= 9>   Master of Ceremonies  </option>
              <option name= nothing value= 10>    Cleaning up   </option>
              <option name= nothing value= 11>    Others        </option>

             </select>"



              ." </td>


             </tr>";




             echo '

             </table>
             <br/>

             <div align="center">
             <input type="submit" name="submit" value="submit" />
             <input type="reset" value="Clear" />
             <hr> <hr> 
             </div>


             </form>

             ';

///
};



function SelectOption(){
    include('../CIEcon.php');

///
             if(isset($_POST['submit'])){

                        if(isset($_POST['submit']))  // second submit
                        {
                          $errorMessage = "";

                           if(($_POST['lists'])== 0)  // trying to get error if user don't choose.
                              {
                                $errorMessage .= "<li>You Forgot to Choose !</li>";

                              }

                              $lists = $_POST['lists'];  // <-save info in variable based on user input 

                              if(!empty($errorMessage)) 
                              {
                                echo("<p>There was an error with your form:</p>\n");
                                echo("<ul>" . $errorMessage . "</ul>\n");
                                die();
                              } 

                            } // end of second submit 




                            switch($lists)
                            {
                                case '1':
                                   $GLOBALS['$table']  ="Advertising";
                                break;
                                case '2':
                                  $GLOBALS['$table'] ="Fiscal";
                                break;
                                case '3':
                                    $GLOBALS['$table']="Food";
                                break;
                                case '4':
                                   $GLOBALS['$table'] ="Shopping";
                                break;
                                case '5':
                                    $GLOBALS['$table'] ="Rentals";
                                break;
                                case '6':
                                    $GLOBALS['$table'] ="SettingUp";
                                break;
                                case '7':
                                   $GLOBALS['$table'] ="Performances";
                                break;
                                case '8':
                                    $GLOBALS['$table'] ="Registration";
                                break;
                                case '9':
                                    $GLOBALS['$table'] ="MasterOfCeremonies";
                                break;
                                 case '10':
                                    $GLOBALS['$table'] ="Cleaning";
                                break;
                                 case '11':
                                    $GLOBALS['$table']="Others";
                                break;

                                default;
                                    echo 'Unsupported category';
                                break;
                            }



                if ($GLOBALS['$table'] != ""){

                            $sql = "SELECT * FROM ". $GLOBALS['$table']. "  ";
                             $result = mysqli_query($dbCIE, $sql) or die(mysqli_error($dbCIE));

//trying this...
$_SESSION["tbl"] = $GLOBALS['$table'];

                  /// NOW DISPLAY ALL INFO FROM CHOSEN DATABASE...///

                            echo "
                            <form action= 'Delete.php'  method = 'post'>

                            <table cellpadding ='4' border='1' width='80%' align='center'>
                            <tr>

                            <th>Check </th>
                            <th>Job's Name</th>
                            <th>Description</th>
                            <th> No Students needed</th>
                            <th>Due Date</th>
                            </tr>";

                            while($row = mysqli_fetch_array($result))
                            {
                                echo "<br>";
                            echo "<tr>";
                            echo "<td> <input type='checkbox'  name='Id[]'  value='". $row['Id'] ."' /> </td>";
                           // echo "<td> <input type='checkbox'  name='Table[]'  value='". $GLOBALS['$table'] ."' /> </td>";

                            echo "<td>" . $row['JobName'] . "</td>";
                            echo "<td>" . $row['Description'] . "</td>";
                            echo "<td>" . $row['NoStudent'] . "</td>";
                            echo "<td>" . $row['DueDate'] . "</td>";
                            echo "</tr>";


                            }




                            echo "</table>";
                   /// END THE SEARCH HERE...........///

                            echo " <br>
                                <div align='center'>
                                <input type='reset' value='clear' > 

                                <input type='submit' name='delete' value='delete'>

                                </div>

                            </form>";




                            }  // End if !table=""; 


             } else {  }



///
};// end of function SelectOption

Answer 1

我看到您已经在尝试使用 session 变量的概念。方法如下:

在您的 PHP 文件的最顶部，就在这一行的下方:

$GLOBALS['$table']="";

添加这个:

session_start();
if (isset($_SESSION['table'])) {
    $GLOBALS['$table'] = $_SESSION['table'];
}
// rest of your PHP code...

然后在 SelectOption 函数中，紧接着:

switch($lists)
{
...
}

添加以下行:

$_SESSION['table'] = $GLOBALS['$table'];

通过这种方式，您可以在请求中保持所选表的有效性。

不过，我会敦促您重写代码，更好地将输出 HTML 的部分与初始化变量和执行 SQL 的部分分开。将这两者分开得越好，维护代码就越容易。