如何从PHP函数运行JavaScript AJAX请求？

Question

Currently the success of my PHP if statement just reloads the page:

header('Location: index.php');

Added: link to the site here http://marmiteontoast.co.uk/fyp/login-register/index.php

However I want to run a JavaScript basic AJAX request instead to load a page register-success.php into the div:

function loadSuccess()
{var xmlhttp;
if (window.XMLHttpRequest)
  {xmlhttp=new XMLHttpRequest();}
else
  {xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");}
xmlhttp.onreadystatechange=function()
  {if (xmlhttp.readyState==4 && xmlhttp.status==200)
    {document.getElementById("login-register-wrapper").innerHTML=xmlhttp.responseText;}}
xmlhttp.open("GET","register-success.php",true);
xmlhttp.send();}

However I am unsure about this combination of JavaScript and PHP and how to implement it

1) Is there some sort of PHP function I can wrap around a piece of JS to make it enact it?

2) Is there a way to do a simple AJAX call like this in PHP instead? Or something that mimics it?

Here is the function that validates my form. If the form validates, I need to reload with AJAX and call in register-success file

<?php
    session_start();
    require 'functions.php';

    if(isset($_POST['sign-up'])){
        // username
        if (isset($_POST['username'])){
            $username = mysql_real_escape_string(trim($_POST['username']));
            $_SESSION['status']['register']['username'] = $username;

            if(strlen($username) > 3){
                    if(strlen($username) < 31){
                        if(user_exists($username) === true){
                            $_SESSION['status']['register']['error'][] = 'That username is already taken. Sorry, please try again with a different username.';
                        } else{
                            // passed
                            // continue
                        }
                    } else {
                        $_SESSION['status']['register']['error'][] = 'The username is greater than 30 characters.';
                    }
                } else {
                    $_SESSION['status']['register']['error'][] = 'The username is less than 3 characters.';
                }
        } else {
            $_SESSION['status']['register']['error'][] = 'The username is not entered.';
        }

        if (isset($_POST['password'])){
            $password = mysql_real_escape_string(trim($_POST['password']));

            if(strlen($password) >= 8){
                    $password = hash_function($password);
                } else {
                    $_SESSION['status']['register']['error'][] = "Your secret password is too short. You should make a password with at least 8 letters.";
                }

        } else {
            $_SESSION['status']['register']['error'][] = "You haven't put in a password.";
        }

        // Email address
        if (!empty($_POST['email_address'])){
            $email_address = mysql_real_escape_string(trim($_POST['email_address']));
            $_SESSION['status']['register']['email_address'] = $email_address;
            if(strlen($email_address) > 10){ // email address less than 10
                    if(strlen($email_address) < 161){ // if longer than 160

                        if(email_valid($email_address) == false){ // email address invalid format
                                $_SESSION['status']['register']['error'][] = "The email address has been put in wrong. Please check and try again.";
                            }
                            else{
                                // passed min length, passed max length, passed validation
                                // Continue
                            }
                    }
                    else 
                    {
                        $_SESSION['status']['register']['error'][] = 'The email address is too long.';
                    }
                } 
                else
                {
                    $_SESSION['status']['register']['error'][] = "The email address is too short. It can't be shorter than 10 letters.";
                }
        }
        else{// passed (no email input)
        }

        if (isset($_POST['tos'])){
            $_SESSION['status']['register']['tos'] = $_POST['tos'];
            if(empty($_SESSION['status']['register']['error'])){
                if(register($email_address, $username, $password) === true){

                    // Success!!
                    $_SESSION['status']['register']['success'] = true;

                    // Sends an email

                    send_email($email_address);

                } else {
                    echo mysql_error();
                    die();
                    $_SESSION['status']['register']['error'][] = "Something went wrong. We're sorry. Please try again.";
                }
            } else {}
        } else {
            $_SESSION['status']['register']['error'][] = "You have to agree to the House Rules to be able to sign up.";
        }

        header('Location: index.php');
    } else {
        // success script with AJAX goes here
    }

    ?>

Answer 1

You need to write javascript code outside PHP Block, so after ?>. Ajax call are made from client side, so only with javascript.

To simplify your code, you can use a javascript lib, like jQuery, so the code is more simple:

$('#login-register-wrapper').load('register-success.php');

You can made this with PHP like Kamehameha Answer, using ob_get_contents().

In this case, without parameters from html page, the result is the same, the content from processed.

Edit:

Based in comments, you need to redirect to 'index.php' with some parameter, like:

header('Location: index.php?success=1');

So, in index.php, you can write some like this:

if (isset($_GET['success']) && $_GET['success'] == 1) {
    echo '<script>function loadSuccess()
{var xmlhttp;
if (window.XMLHttpRequest)
  {xmlhttp=new XMLHttpRequest();}
else
  {xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");}
xmlhttp.onreadystatechange=function()
  {if (xmlhttp.readyState==4 && xmlhttp.status==200)
    {document.getElementById("login-register-wrapper").innerHTML=xmlhttp.responseText;}}
xmlhttp.open("GET","register-success.php",true);
xmlhttp.send();}</script>';
}

Edit:

In tag body, you need to call javascript function loadSuccess(). Like this:

<body onload="loadSuccess()">

Answer 2

You would simply have to create a extra .php file that only has the register-logic in it. Assuming you have a form with all the data in it, you would then use javascript to make a submit button and send all the data (for example via get or post) to this .php file on your server using a ajax request. answer would only be the html you want to include in your wrapper. This response from the server would then simply be displayed by modifying the dom of your current site

Answer 3

It's really simple ! do the following :

• Add this line to your php code so it can run on the success of your PHP Function :

echo " document.getElementById('success').click(); ";

• Now add this HTML line into your page , so it can load the

 <a id="success" style="visibility:hidden;">Success</a> <script> var el = document.getElementById('success'); el.onclick = loadSuccess(); </script>