Send message from php to ajax with 'echo json_encode' not working

Question

I'm trying to send a message from php to ajax. I'm using echo json_encode to do it. When I do that, the website displays the arrays message. ( {"foo":"content of foo"} ). How can I get it to not display the message?

Also, the alerts from ajax don't get called.

Here's the code:

<?php
$myString = $_POST['data'];

if ($myString == "") {
    echo json_encode(
      array()
      );

} else if ($myString == "foo" {
    echo json_encode(
      array(
        'foo2' => 'this is the contents of foo'
        )
      );
} else if ($myString == "foo2") {
    echo json_encode(
      array(
        'foo2' => 'this is the contents of foo2'
        )
      );
}
?>


<script>
  var formData = new FormData($(this)[0]);
  $.ajax({
    url: $(this).attr("action"),
    context: document.body,
    data: formData, 
    type: "POST",  
    contentType: false,
    processData: false,
    success: function(response) {
      if (response.length == 0) {
          alert("empty");
      } else if (response.foo) {          
          alert("foo");
      } else if (respons.foo2) {
          alert("foo2");
      }          
    }
  });           
</script>

How can I get the array to not display on the website? And why are the ajax if statements not getting called?

Answer 1

You need to set the HTTP header at the top of the script so you can return son:

header('Content-type: application/json');

Your script is a little confusing. You can't return json AND html/javascript.

It's one or the other.