如何使用Mysql和PHP插入多个具有相同名称的行

Question

I have a database called dbcenter and I Have Courses table. I have form to insert multiple courses names at the same time. But when I do submit it only insert one empty row. This is my input FORM :

    <form action="COURSE.php" method="POST" enctype='multipart/form-data'>

        <input type="text" name="listName[]" value="course 1">
        <input type="text" name="listName[]" value="course 2">
        <input type="text" name="listName[]" value="course 3">

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

And my PHP code:

if(isset(filter_input_array(INPUT_POST)['submit'])){

   $names[] = filter_input(INPUT_POST,'listName');

   if(is_array($names)){
      foreach ($names AS $key => $item){

        $insertCourse = $con->prepare("INSERT INTO `courses`(`course_Name`) 
        VALUES ('$item')");
        }
        $insertCourse->execute();
                if($insertCourse){
                    echo 'added';
                    }
                }
   else {
        echo 'not array';
      }
}

I tried to remove [] from input names listName[],and it inserts data but only last textbox. Any one can help me in this ?

Answer 1

There is error in filtering input.

execute() should be inside foreach loop.

Also never trust user input, use parameterized queries or escape with mysqli::real_escape_string(), so that user input is properly escaped:

   if(isset(filter_input_array(INPUT_POST)['submit'])){

       $names = filter_input_array(INPUT_POST)['listName'];

       if(is_array($names)){
          $insertCourse = $con->prepare("INSERT INTO `courses`(`course_Name`) 
               VALUES (?)");
          $insertCourse->bind_param("s", $item);
          foreach ($names AS $key => $item){

              $res = $insertCourse->execute();
              if($res){
                  echo 'added<br>';
              }
          }
          $insertCourse->close();
       }
       else {
           echo 'not array';
       }
   }