使用Ajax更新MySQL数据库

Question

I'm trying to send a JS array to a .php file on the click of a button, and run the php file's code on the click, using the array that was sent.

I have a button:

<button id="submit" class="button1" >Submit<span></span></button>

Which I try to run this JS ajax with:

$('#submit').click(function() {
  $.ajax({
    method: "POST",
    url: "submit.php",
    data: selectedImageArray
  }).done(function( msg ) {
    alert( "Data Saved: " + msg );
  });
});

In my submit.php file, I connect to the database, then have this:

    $array = $_POST['selectedImageArray'];

    $sql = $dbh->prepare("INSERT INTO pending_trades (steam_id, trade_items, is_giving, is_receiving, has_started) VALUES (:steamid, :itemlist, '1', '0', '0')");

    $sql->bindParam(':steamid', $steamprofile['steamid']);
    $sql->bindParam(':itemlist', $array);

    $sql->execute();


}

When I click the "submit" button, I get the message saying "Data saved", but nothing is happening with my database. Should clicking the button run the submit.php code?

Answer 1

You have a syntax error with your JS. Also, since #submit is an ID, qualifying it with button is unnecessary.

Your code should read:

$('#submit').click(function() {
  $.ajax({
    method: "POST",
    url: "submit.php",
    data: selectedImageArray
  }).done(function( msg ) {
    alert( "Data Saved: " + msg );
  });
});

Edit 1:

I see that you have incorporated the above code into your JS. Now on to your problem on the server side (PHP/SQL).

Firstly, why are you decoding $_POST[selectedImageArray] then re-encoding it? Doesn't make sense to me.

Secondly, what is the value of $steamprofile['steamid'] ?

Thirdly, what is the schema of your SQL table? Are you sure you're not violating any unique / not null / fk constraint?

Do yourself a favour, and use a debugging/logging solution on the server-side. It can be as simple as printing debug lines into a log file so you can inspect later on to find out what is happening.

What I'd do:

• check value of $_POST[selectedImageArray] . It should be a string.
• check the value for $array . It should be an array.
• read the error logs to see what else it says.
• $sql->execute(); returns a bool (TRUE on success). Use it in your script to return either success or failure message.
• Log down the value of $sql->errorCode(); on failure.

With all the above, you should have enough to troubleshoot what went wrong there.

Answer 2

$('#submit').click(function(){
  $.ajax({
      method: "POST",
      url: "submit.php",
      data: {selectedImageArray: selectedImageArray}, // this is supposed to be JSON
      .done(function( msg ) {
        alert( "Data Saved: " + msg );
      });
  });
});

And

$_POST['selectedImageArray'] // see the quotes

Answer 3

I suppose that steam_id is a primary key with auto increment, so if you are trying to insert a row to database with the same value for steam_id , then it is a possibility that your data cannot be added.

To debug in a better way, try to generate the query in the server and echo it. Then try to run the same query in your MySQL console to find the response.