Json_encoding Ajax请求中的Php变量

Question

Currently I am using a jQuery Ajax asynchronous function to request a PHP page multiple times until a large number of spreadsheet rows are processed. Right now I am using the following code to set the variables to be passed to the requested page, I am not sure if this is the proper way to do it or not. PHP:

if($_SERVER['REQUEST_METHOD'] == 'POST') {
    $new_spreadsheet = nl2br($_POST['spreadsheet']);
    $new_spreadsheet = explode('<br />', $new_spreadsheet);
    array_shift($new_spreadsheet);
    $new_spreadsheet = array_values($new_spreadsheet);
    $new_spreadsheet = json_encode($new_spreadsheet);
    echo var_dump($new_spreadsheet);
}

JavaScript/PHP:

var done = false,
offset = 0,
limit = 20,
rankings_abv_twenty = 0,
sum = 0,
num_count = 0,
websites = 1
<?php if($_SERVER['REQUEST_METHOD'] == 'POST') {
    echo ', spreadsheet = '.$new_spreadsheet;
}?>;

On the requested PHP page (which happens to be Object-Oriented PHP), I have the following code to slice off 20 rows to process on the given request. Please not the PHP is a full working class, I just did not include all the PHP for the sake of post length. Also note, I have another page which calls the class, which passes the spreadsheet variable to the constructor of the PHP by reference as $_POST['spreadsheet'], so I know I have the right value as the spreadsheet. PHP:

$this->offset = $offset;
$this->limit = $limit;
$this->spreadsheet = json_decode($spreadsheet);

Here is the PHP line which slices off the rows:

$this->rows = array_slice($this->spreadsheet, $this->offset, $this->limit);

For some reason my code is not working properly and is giving me the following errors relating to the above code:

PHP Warning:  json_decode() expects parameter 1 to be string, array given
PHP Warning:  array_slice() expects parameter 1 to be array, null given

I think it might have something to do with how my string is getting passed the requested PHP. Also, just as a further note, when I use var_dump() on my spreadsheet variable before it is passed to the requested PHP, I get it outputted as a string like so:

string(7560) "String content goes here"

Answer 1

On the first look, instead of echoing the json_encode, you used var_dump.

And when manually modifying the json encoded string make sure to use " around the vars.

And this:

  websites = 1
  <?php if($_SERVER['REQUEST_METHOD'] == 'POST') {
    echo ', spreadsheet = '.$new_spreadsheet;
   }?>;

Will result in:

  websites = 1, spreadsheet = "{"1":"foo","2":"bar","3":"baz","4":"blong"}";

Wrap the line in ' if that's what you expect it..

like this:

 echo ", spreadsheet = '".$new_spreadsheet."'";