PHP retrieve data from db in multi queries and print json [duplicate] - php

Question

Right now I have this PHP:
$columns = array(*/Data*/);
echo json_encode($columns);
And this is sent through an AJAX GET request with JQuery.
var columns = jQuery.parseJSON(response);
I would like to be able to send more than one array in the json_encode() is there any way to do this and how would you parse it with jQuery?

Answer 1

Sure, you could send an array of array. PHP associative array will become a javascript object.
In PHP:
$data = array();
$data['fruits'] = array('apple','banana','cherry');
$data['animals'] = array('dog', 'elephant');
echo json_encode($data);
and then on jQuery
var data = jQuery.parseJSON(response);
then you could then do something like this to access the values
console.log(data.fruits[0]); // apple
console.log(data.animals[1]); // elephant

Answer 2

The code should be like the following:
$columns = array(/*Data*/);
$columns1 = array(/*Data1*/);
echo json_encode(array($columns,$columns1));
in jQuery use
var columns_array=jQuery.parseJSON(response);
columns=columns_array[0];
columns1=columns_array[1];

Answer 3

$data1 = array();
$data2 = array();
$data1[] = array('apple','banana','cherry');
$data2[] = array('dog', 'elephant');
echo json_encode(array($data1,$data2));
in ajax,
console.log(response[0][0])//apple
console.log(response[1][0])//dog.....

Answer 4

After you have populated all the arrays namely $array1_json, $array2_json etc in my case,
$number_of_array1elements = count($array1_json);
$number_of_array2elements = count($array2_json);
$number_of_array3elements = count($array3_json);
array_unshift($array1_json , $number_of_array1elements);
// pushes element to the start of array1_json
array_unshift($array2_json , $number_of_array2elements);
array_unshift($array3_json , $number_of_array3elements);
and similarly for other arrays.
echo json_encode( array_merge($array1_json, $array2_json, $array3_json) );
In your .js file, use:
var val = xmlhttp.responseText;
var jsonData = JSON.parse(val);
var number_of_array1elements = jsonData[0];
for (var i = 1; i <= number_of_array1elements; i++ )
{
// use jsonData[i] to select the required element and do whatever is needed with it
}
var number_of_array2elements = jsonData[i];
for ( i = i+1; i <= number_of_array1elements+number_of_array2elements+1; i++ )
{
// use jsonData[i] to select the required element and do whatever is needed with it
}