foreach query

[genzedu777]

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

    // Write the questionnaire response rows to the response table

    foreach ($_POST as $response_id => $response) {

      $query = "UPDATE mismatch_response SET response = '$response' WHERE response_id = '$response_id'";

      mysqli_query($dbc, $query);

    }

    echo '<p>Your responses have been saved.</p>';

  }

 

 

Can someone explain this current code? foreach ($_POST as $response_id => $response) {

 

My understanding for 'foreach' function, it will basically run through each line?

 

How about ($_POST as $response_id => $response), why is the $_POST exist?

 

$response_id => $response --- Is the same meaning as $response_id = $response?

 

 

Thanks,

Wilson

[jcbones]

foreach()  is used to process an array.

 

$_POST is always an array.

 

The ($_POST as $response_id => $response) simple tells the foreach loop that you want to grab the key as $response_id, and the value as $response.

 

So if the name of your input was "letter" and you type in "q".

The $response_id is "letter".

The $response is "q".

[genzedu777]

Hi, thanks for the clear explanation

[phant0m]

If you want to update many different rows with different values, you should have a look at MySQL's CASE function. That way you only need to use one query instead of issuing one query per row.

[Daniel0]

Also have a look at http://php.net/foreach

[genzedu777]

Hi,

 

Could I ask one question.

 

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

    // Write the questionnaire response rows to the response table

    foreach ($_POST as $response_id => $response) {

      $query = "UPDATE mismatch_response SET response = '$response' WHERE response_id = '$response_id'";

      mysqli_query($dbc, $query);

    }

    echo '<p>Your responses have been saved.</p>';

  }

 

Why do we need $_POST?

 

Cant we just write the code as without the $_POST? For instance, foreach ($response_id => $response)?

[kenrbnsn]

Did you read the responses and the manual page. Foreach loops through an array. $_POST is the array that holds all the responses from a form.

 

Ken

[genzedu777]

Thanks, I have gotten it