Question

I have this AJAX:

                $.ajax({
                    url : get_base_url() + 'update',
                    type : 'POST',
                    async : false,
                    data : json_positions,
                    dataType : 'html',
                    success : function(data) {
                        console.log(data);
                    },
                    error : function(jqXHR, textStatus, errorThrown) {
                        console.log('error:');
                        console.log(jqXHR);
                        console.log(textStatus);
                        console.log(errorThrown)
                    }
                });

data sent is:

json_positions

which is a string like this:

{"new_positions" : [{ "id": "2", "position": "0"},{ "id": "5", "position": "1"},{ "id": "4", "position": "2"}]}

I want to decode json_positions using json_decode() in a PHP page but it seem that tdata is not sent to the php page because when i try to:

print_r($_POST);

it returns an empty array using console.log(data).

Answer 1

Well your code is okay, no need to change anything. But it’s how you pass your data.

data sent is: json_positions which is a string like this: …

You should not pass it like string. It should be an object like you defimed it:

{"new_positions" : [{ "id": "2", "position": "0"},{ "id": "5", "position": "1"},{ "id": "4", "position": "2"}]}

Make you sure you pass an object, not string, e.g. don’t add any quotes around it etc. Then it’s going to work fine.

EDIT

As per jQuery documentation for $.ajax data parameter:

dataObject, String
Data to be sent to the server. It is converted to a query string, if not already a string. It’s appended to the url for GET-requests. See processData option to prevent this automatic processing. Object must be Key/Value pairs. If value is an Array, jQuery serializes multiple values with same key based on the value of the traditional setting (described below).

So your data should be a query string or an object.

In your case I recommend to use object. Like with this code:

var json_positions = {
    new_positions: []
};
$.each(result, function(key, value) {
    var value_splitted = value.split('-');
    json_positions.new_positions.push({
        id: value_splitted[1],
        position: key
    });
});