I have done some research regarding on how to use file_get_content with post. And I have also read this one which is I honestly don't understand since I am not that familiar with PHP. Below is my php code in getting my json and used it for my ajax request, using methog GET.:
<?php 
    echo(file_get_contents("http://localhost:8001/" . $_GET["path"] . "?json=" . urlencode($_GET["json"])));
?>
Now, I am using method POST and I dont know how to modify my php code to post my data from my javascript. Below is my data which I wanted to post in my url request (that is also what I used as json in method GET):
{"SessionID":"9SQLF17XcFu0MTdj5n",
  "operation":"add",
  "transaction_date":"2011-7-28T00:00:00",
  "supplier_id":"10000000108",
  "wood_specie_id":"1",
  "lines":  [{"...":"...","..":"..."},{"...":"...","..":"..."}],
  "scaled_by":"SCALED BY",
  "tallied_by":"TALLIED BY",
  "checked_by":"CHECKED BY",
  "total_bdft":"23.33",
  "final":"N"}
I just need to change this code
echo(file_get_contents("http://localhost:8001/" . $_GET["path"] . "?json=" . urlencode($_GET["json"])));
with POST to send my post my data.
EDIT: I need to produce a request like this:
http://localhost/jQueryStudy/RamagalHTML/processjson.php?path=getData/supplier?json={"SessionID":"KozebJ4SFqdqsJtRpG6t1o3uQxgoeLjT"%2C"dataType":"data"}
 
     
     
     
    