我想在多列但同一个表中插入多个复选框值

Question

My code inserts multiple selected values into two columns but both columns hold the value of the first listed(selected) checkbox. eg. if i selected .Net2 and Java3 two cloumns will be affected but both holds the value of 2.

<form action="" method="post" >  
   <div style="width:200px;border-radius:6px;margin:0px auto">  
<table border="1">  
   <tr>  
      <td colspan="2">Select Technolgy:</td>  
   </tr>  
   <tr>  
      <td>PHP1</td>  
      <td><input type="checkbox" name="techno[]" value="1"></td>  
   </tr>  
   <tr>  
      <td>.Net2</td>  
      <td><input type="checkbox" name="techno[]" value="2"></td>  
   </tr>  
   <tr>  
      <td>Java3</td>  
      <td><input type="checkbox" name="techno[]" value="3"></td>  
   </tr>  
   <tr>  
      <td>Javascript4</td>  
      <td><input type="checkbox" name="techno[]" value="4"></td>  
   </tr>  
   <tr>  
      <td colspan="2" align="center"><input type="submit" value="submit" name="sub"></td>  
   </tr>  
</table>  
</div>  
</form>  
<?php  
if(isset($_POST['sub']))  {  
    $connection = mysqli_connect("localhost", "root", ""); // Establishing Connection with Server
    $db = mysqli_select_db($connection, "ofobms"); // Selecting Database from Server
    // Check connection
    if (!$connection) {
        die("Connection failed: " . mysqli_connect_error());
    }  
$checkbox1=$_POST['techno']; 
//$hobb= $_POST['Hobbies']; 
$chk="";  
foreach($checkbox1 as $chk1)  
   {  
      $chk .= $chk1.",";   
   }  

   $N = count($checkbox1);
   echo("<p>You selected $N techno(s): ");
   for($i=0; $i < $N; $i++)
   {
    $in_ch=mysqli_query($connection,"INSERT INTO order_table (item_ID)
    values ('$chk')"); 
   } 

if($in_ch==2)  
   {  
      echo'<script>alert("Inserted Successfully")</script>';  
   }  
else  
   {  
      echo'<script>alert("Failed To Insert")</script>';  
   }  
}  
  ?>

this is what my current table looks like

| item_ID |
|    2      
|    2

i want it to be like this, for the second column to hold the value 3

| item_ID |
|    2      
|    3      

Answer 1

You shouldn't be concatenating all the checkbox values. Each INSERT query needs to insert just the current element of $checkbox. You should also use a prepared statement to protect against SQL injection.

You also don't need two loops, just one.

Also, mysqli_query() returns either TRUE or FALSE when it's executing an INSERT query, I'm not sure why you're comparing it to 2.

$N = count($checkbox1);
echo("<p>You selected $N techno(s): ");
$stmt = mysqli_prepare($connection, "INSERT INTO order_table (item_ID) values (?)");
mysqli_stmt_bind_param($stmt, "i", $chk1);
$success = true;
foreach($checkbox1 as $chk1) {
    if (!mysqli_stmt_execute($stmt)) {
        $success = false;
        break;
    }
}
if($success)  
{  
    echo'<script>alert("Inserted Successfully")</script>';  
}  
else  
{  
    echo'<script>alert("Failed To Insert")</script>';  
}