通过 POST 将数据从 javascript 传递到 PHP 不起作用

Question

Im trying to send an array, populated using javascript on client-side, to a php file in the backend.

MAIN.JS

    var list = iterateItems();
  _ajax("https://127.0.0.1/prog1/final/class/ticket.php", list)
  .done(function(list){});
  });
  function _ajax(url,data) {
    var ajax = $.ajax({
      type : "POST",
      datatype : "string",
      url : url,
      data : data
    })
    return ajax;
  }
  
  
  function iterateItems() {
    // array is an array populated in this function, returned to be sent to ticket.php
    return JSON.stringify( array );
  };

TICKET.PHP

<?php
   var_dump(json_decode($_POST['list']));
?>

And executing this, I'm getting this result:

Notice: Undefined index: list in D:\127.0.0.1/prog1/final/class/ticket.php on line 2
NULL

Im not understanding why im getting an undefined index. I tried googling this, but most responses seem to point in the direction of using some kind of HTTPS method, which is what I'm trying to achieve via POST. Any help will be greatly appreciated. Thank you.

Answer 1

The 'list' undefined issue might be due to the structure of the JSON array you pass.

Try the below code and check if it works. If not let's check further :)

 var list = {'list': iterateItems()}; _ajax("https://127.0.0.1/prog1/final/class/ticket.php", list) .done(function(list){}); }); function _ajax(url,data) { var ajax = $.ajax({ type : "POST", datatype : "json", url : url, data : data }) return ajax; } function iterateItems() { // array is an array populated in this function, returned to be sent to ticket.php return JSON.stringify( array ); };

Your PHP Code:

<?php

   var_dump(json_decode($_POST['list']));

Answer 2

PHP can't parse JSON parameters automatically. $_POST will only be filled in from a URL-encoded string or a FormData object.

$.ajax will URL-encode an array automatically for you.

_ajax("https://127.0.0.1/prog1/final/class/ticket.php", array)
  .done(function(list) {});

function _ajax(url, data) {
  var ajax = $.ajax({
    type: "POST",
    dataType: "string",
    url: url,
    data: {list: data}
  })
  return ajax;
}

In PHP you then don't need to call json_decode() . The value of $_POST['list'] will be the array.

Answer 3

after you call var list = iterateItems(); add this list = 'list=' + list; the php file would then recognize the index list.