请教我的代码中的问题 ajax+php(CodeIgniter)

我用ajax将页面的值传递到后台，但是却无法获取，请教下我这个该怎么写呢？麻烦大牛们了。

我的页面代码为：
<script> <br /> $(function() { <br /> $("form[name='estimate']").submit(function(e) { <br /> e.preventDefault(); <br /> var btn = $("form[name='estimate']").find("input[type='submit']"), <br /> price = $(this).find(".price"); <br /> btn.button('loading'); <br /> price.html(""); <br /> $.ajax({ <br /> type: "POST", <br /> url: '<?php echo base_url(); ?>index.php?module=testprice&view=getprice', <br /> data: $(this).serializeArray(), <br /> success: function(data) { <br /> price.html("<h3>$" + data + " RMB<h4>" + ""); <br /> btn.button('reset'); <br /> }, <br /> error: function() { <br /> alert("Service Unavailable"); <br /> } <br /> }); <br /> }); <br /> <br /> </script>    

    

        

            

                

                    

                        

                            

估算

                        

                    

                    

                        

                            

                                

计算成本

                                

                                    

                                        

                                            

                                                
                                                     公制的 (kg, cm)
                                                
                                                  
                                                
                                                     英制的 (oz, in)
                                                
                                            

                                        

                                    

                                

                                

                                    

                                        

                                            邮政编码
                                            

                                                
                                            

                                        

                                    

                                    

                                        

                                            

                                                重量
                                                

                                                    

                                                        
                                                        kg
                                                    

                                                

                                            

                                        

                                        

                                            尺寸
                                            

                                            

                                                
                                                cm
                                            

                                            x
                                            

                                                
                                                cm
                                            

                                            x
                                            

                                                
                                                cm
                                            

                                        

                                    

                                

                                

                                    

                                        

                                            

                                                
                                                     fsd
                                            

                                        

                                    

                                    

                                

                            

                            

                                
                                

                                

                            

                        

                    

                

            

        

我的后台代码如下：
 function getUserPrice() {
        $tozipcode_t = $_POST('postal_code');

}

我这里无论怎样都无法获取值，请大牛帮忙分析一下，多谢多谢了

回复讨论(解决方案)

$tozipcode_t = $_POST['postal_code'];

十分感谢。我真的很多不会，以后多和您请教了。