下拉值不会插入mysql中

Question

在这段代码中，下拉值没有插入到mysql数据库中.exit_name插入到course_code col中，而course_code值没有插入到mysql中。所以有人请帮帮我。当testcourse被选中时，exam_name将从examcourse中填充相应的exam_name的course_code将从exam_course显示。

upload2_view.php

       <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script>
      <script type="text/javascript">
         $(document).ready(function()
             {
          $(".hai").change(function()
            {
          var id=$(this).val();
         // Please find the course_code, course_code was not found
      var dataString = 'course_code='+ id;

       $.ajax
       ({
       type: "POST",
       url: "upload_view2.php",
        data: dataString,
        cache: false,
        success: function(html)
        {
        $(".hai2").html(html);
        } 
        });

        });
        });
      </script>
      </head>



        <form enctype="multipart/form-data" action="<?php echo $_SERVER['PHP_SELF']; ?>"  method="post">

    File to import:<br />

     <input size='30' type='file' name='filename'>

     Select Exam name:<select name=hai class="hai">

     <?php
     mysql_connect("localhost", "root", "") or die("Error connecting to database:   ".mysql_error());

   mysql_select_db("slseatapp") or die(mysql_error());

     $query="select  distinct exam_name from examcourse";
     $result = mysql_query($query);
     while($nt=mysql_fetch_array($result)) {
      echo "<option value='".$nt['exam_name']."'>".$nt['exam_name']."</option>";
      }

      ?>
     </select>




<input type="submit" name="submit" value="Upload"></form>



 <?php 

   mysql_connect("localhost", "root", "") or die("Error connecting to database: ".mysql_error());

 mysql_select_db("slseatapp") or die(mysql_error());

//Upload File 
  if (isset($_POST['submit'])) { 
  if (is_uploaded_file($_FILES['filename']['tmp_name'])) { 




 //Import uploaded file to Database 
   $row = 1; 
   $handle = fopen($_FILES['filename']['tmp_name'], "r"); 
   $var = $_POST['hai'];
    $var1 = $_POST['hai2'];




   while (($data = fgetcsv($handle, 1000, ",")) !== FALSE) { 

  //Update Database Values 

   $import="insert into student_table  (id,register_number,name,course_code,subject_code,exam_name) VALUES('".mysql_real_escape_string($data[0])."', '".mysql_real_escape_string($data[1])."','".mysql_real_escape_string($data[2])."','$var','$var1','$var2')"; 
   $import="replace into  student_table (id,register_number,name,course_code,subject_code,exam_name) VALUES('".mysql_real_escape_string($data[0])."', '".mysql_real_escape_string($data[1])."','".mysql_real_escape_string($data[2])."','$var','$var1','$var2')";


    mysql_query($import) or die(mysql_error()); 
   } 
   }
  fclose($handle); 
   echo"<script>alert('Uploaded Successfully');</script>";

 } 
  ?>
<br />

upload_view2.php

<?php

          mysql_connect("localhost", "root", "") or die("Error connecting to database:   ".mysql_error());

       mysql_select_db("slseatapp") or die(mysql_error());
?>

         <form enctype="multipart/form-data" action="<?php echo $_SERVER['PHP_SELF']; ?   >" method="post">


 <?php

        @$exam_name=$_POST['course_code'];
           ?>

        Course code:<select name="hai2">

          <?php

       $query="SELECT distinct course_code FROM examcourse where exam_name = '$exam_name' ";

         $result = mysql_query($query);
    while($nt=mysql_fetch_array($result)) {
         echo "<option value='".$nt['course_code']."'>".$nt['course_code']."</option>";
     }
          ?>

</select>
<br />