我无法在javascript代码中调用我的php函数

Question

我正在使用PHP使用注册页面并使用JQuery验证我的注册表单...当我在JQuery代码中调用我的PHP函数时，我无法获得我的输出.... 当用户用适当的格式填充所有字段然后在数据库中插入数据的php注册函数调用时，我想这样做

这是PHP和JQUERY的代码

<?php
    function signup(){
        $name=$_POST["name"];
        $lastname=$_POST["lastname"];
        $mail=$_POST["mail"];
        $pass=$_POST["pass"];
        $repass=$_POST["repass"];
        $country=$_POST["country"];
        $city=$_POST["city"];
        $day=$_POST["day"];
        $month=$_POST["month"];
        $year=$_POST["year"];
        $gender=$_POST["name"];

        //echo $name." ".$lastname." ".$pass." ".$repass." ".$mail." ".$country." ".$city." ".$day." ".$month." ".$year." ".$gender;
    }
  ?>

<script>
$(document).ready(function(){
    $("#reg-btn").click(function () {
        var name = $("#name").val();
        var lastname = $("#lastname").val();
        var mail = $("#mail").val();
        var pass = $("#pass").val();
        var repass = $("#repass").val();
        var country = $("#country").val();
        var city = $("#city").val();
        var day = $("#day").val();
        var month = $("#month").val();
        var year = $("#year").val();
        var gender = $("#gender").val();
       if( !$('#name').val() ||  !$('#lastname').val() || !$('#mail').val() || !$('#pass').val() || !$('#repass').val() || !$('#country').val() || !$('#city').val() || !$('#day').val() || !$('#month').val() || !$('#year').val() || !$('#gender').val()) {
            $("#error").html("Please Fill all Fields");
            return false;
    }else{
            var emailRegex = /^([\w-\.]+)@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([\w-]+\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)$/;
            var nameRegex=/^[a-zA-Z ]+$/;
            var passRegex=/^(?=.*\d)(?=.*[a-z])(?=.*[A-Z])[0-9a-zA-Z]{8,}$/;
            if(nameRegex.test(name)){
               if(nameRegex.test(lastname)){
                   if(emailRegex.test(mail)){
                       if(passRegex.test(pass)){
                           if(repass==pass){
                               if(nameRegex.test(country)){
                                   if(nameRegex.test(city)){
                                       <?php signup();?>
                                   }else{$("#error").html("invalid City Name");return false;};
                               }else{$("#error").html("invalid Country Name");return false;};
                           }else{$("#error").html("Passwords do not Match");return false;};
                       }else{$("#error").html("invalid Password");return false;};
                   }else{$("#error").html("invalid Email Address");return false;};
               }else{$("#error").html("invalid Last Name");return false;};
            }else{$("#error").html("invalid First Name");return false;}
        }
    });
});

</script>