Json unable to pass array to php - php

Question

As the title says, I failed to pass the data array via json ajax to php. I am using codeigniter, what did I do wrong? here is the jQuery code:
function load_page_data1(){
var data = [];
data['val'] = "solid_t1";
$.ajax({
type: 'POST',
url: BASE_URL+'index.php/Chart_varnish/getdata',
data: data,
dataType: 'json',
success: function(output) {
alert(output);
},
error: function(request, status, error){
alert("Error: not working");
}
});
}
Here is the php code:
function getdata(){
$parameter = '';
if(isset($_POST))
{
if(isset($_POST['val']))
{
$parameter = $_POST['val'];
} else
{
echo "failed!";
}
}
$this->load->model('Chart');
$this->load->helper('url');
$data1 = $this->Chart->getdata_solid($parameter);
echo json_encode($data1);
}
Final:
Guys, it turn out that the values did passed from jQuery to php, the problem is that I stupidly call the same php function twice within the javascript function, then the second time calling without posting the 'val', so that the php function error and stop.
Thank you all for your answers, at least I learn the different ways to passing data by using jQuery.

Answer 1

Don't make a array if it's not a array just make a object
var data = {};
data.val = "solid_t1";
// equivalent to
data ={val:"solid_t1"};
// equivalent to
data['val'] ="solid_t1";
$.ajax({
type: 'POST',
url: BASE_URL+'index.php/Chart_varnish/getdata',
data: data,
dataType: 'json',
success: function(output) {
alert(output);
},
error: function(request, status, error){
alert("Error: not working");
}
});
Update 1: if you need to send array you need to make a proper array object like below
Example :
var data=[];
item ={val:'value'};
data.push(item);
var new_data = JSON.stringify(data);
$.ajax({
type: 'POST',
url: BASE_URL+'index.php/Chart_varnish/getdata',
data: new_data,
dataType: 'json',
success: function(output) {
alert(output);
},
error: function(request, status, error){
alert("Error: not working");
}
});
For Debugging :
May be problem with your server side code .so for the testing purpose comment all the line in function just do this echo json_encode($_POST); and in your ajax success function just add console.log(output); and let me know the result.

Answer 2

create one json object
jsonObj = [];
create array list as per your need
item = {}
item ["val"] = "solid_t1";
push the array list in to the json.
jsonObj.push(item);
Please have a try like this. It is working in my case.
Your full code will be like
function load_page_data1(){
jsonObj = [];
item = {}
item ["val"] = "solid_t1";
jsonObj.push(item);
$.ajax({
type: 'POST',
url: BASE_URL+'index.php/Chart_varnish/getdata',
data: jsonObj,
dataType: 'json',
success: function(output) {
alert(output);
},
error: function(request, status, error){
alert("Error: not working");
}
});
}
The another way to use this is given below.
function load_page_data1(){
var jsonObj = {};
jsonObj["val"] = "solid_t1";
$.ajax({
type: 'POST',
url: BASE_URL+'index.php/Chart_varnish/getdata',
data: jsonObj,
dataType: 'json',
success: function(output) {
alert(output);
},
error: function(request, status, error){
alert("Error: not working");
}
});
}

Answer 3

Instead of var data = []; use var data = {}; to initialize your data. It should solve your problem.
Your data wasn't being passed as json, now it will.
Code will be:
function load_page_data1(){
var data = {};
data['val'] = "solid_t1";
$.ajax({
type: 'POST',
url: BASE_URL+'index.php/welcome/getdata',
data: data,
dataType: 'json',
success: function(output) {
alert(output);
},
error: function(request, status, error){
alert("Error: not working");
}
});
}
One more suggestion please use CI input library for post request in controller.
e.g.
$parameter = $this->input->post('val');