Develop Reference

Posting js variables to PHP not running in any method

In my JS code, I take in 3 inputs on a html page and save them to local storage. I then want to send these variables to php in order to save them to my database. No matter how hard I try no tutorial using ajax, jquery etc allows me to successfully post and echo variables from javascript in my php code. I see no reason why my code below doesn't echo the variables, but it doesn't.
Full code: https://codeshare.io/ayvK9e
Exact PHP elements (just trying to send normal variables right now as it still won't work"
PHP:
foreach($_POST as $post_var){
echo($post_var);
}
JS:
const xhr = new XMLHttpRequest();
xhr.onload = function(){
const serverResponse = document.getElementById("serverResponse");
serverResponse.innerHTML = this.responseText
};
xhr.open("POST", "eDBase.php");
xhr.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
xhr.send("name=dominic&message=bumbaclaat");

If $post not work try using input php
$data = json_decode(file_get_contents('php://input'), true);

When calling my function with the inputs onclick=showFunction; I was passing nothing to the function. In order for my values to be echoed in php I had to pass a parameter to the function onclick=function('text or variable'); IDK how I missed that.

Try using the FormData()
let form = new FormData();
form.append('name', 'dominic');
form.append('message', 'bumbaclaat');
const xhr = new XMLHttpRequest();
xhr.open("POST", "eDBase.php");
xhr.onreadystatechange = function(){
if(xhr.readyState === XMLHttpRequest.DONE && xhr.status === 200) {
const serverResponse = document.getElementById("serverResponse");
serverResponse.innerHTML = this.responseText;
}
else console.log('error')
};
xhr.send(form);
Comment out the setRequestHeader to test it.
And at PHP
if(isset($_POST['name'])){
echo $_POST['name'];
echo $_POST['message'];
}
else{
echo 'There was a problem';
}

how to send data to php file then echo a message

I am trying to send data to php file then echo the word "Hello!" when i call a function in javascript, however, no message appear, i guess there is en error in the calling, can you guide me please?
Here is my code:
Javascript:
function asyncpost_deviceprint() {
var xmlhttp = false;
if (!xmlhttp && typeof XMLHttpRequest!='undefined') {
xmlhttp = new XMLHttpRequest();
}
else if (!xmlhttp) return false;
xmlhttp.open("POST", "http://localhost/Assignment/insert.php", true);
xmlhttp.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
xmlhttp.send("userAgent" + userAgent()); /* fire and forget */
return true;
}
PHP:
<?php
echo "Hello!";
?>

echo "Hello!";
won't display any message because in Ajax request this function sends a respond to Javascript.
If you want to display sth on the screen with PHP instead of Ajax you should use:
window.location.href="path to your php site"
it will redirect you to php file and display Hello!

xmlhttp.onreadystatechange = function () {
if (xmlhttp.readyState === 4) {
if (xmlhttp.status === 200) {
document.body.innerHTML += xmlhttp.responseText;
}
}
};
Add this before xmlhttp.send
It will literally just stick the php echo text after the last thing in the document.

JavaScript Not Returning Data But No Error Either

I am calling a php file that queries my database and returns a result. I have verified that the php file accurately returns the data as needed, but my calling page is not updated from the JavaScript.
What do I need to alter in my syntax below so that the returned value is returned on page?
<script type="text/javascript">
function boostion()
{
var xhr;
if (window.XMLHttpRequest) {
xhr = new XMLHttpRequest();
} else if (window.ActiveXObject) {
xhr = new ActiveXObject("Microsoft.XMLHTTP");
}
xhr.open("GET", "QueryDB.php", true);
xhr.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
xhr.onreadystatechange = display_data;
function display_data() {
if (xhr.readyState == 4) {
if (xhr.status == 200) {
document.getElementById("data").innerHTML = xhr.responseText;
} else {
alert('There was a problem with the request.');
}
}
}
}
</script>
EDIT
I have also opened Developer Options in Chrome and checked the Console and there are no errors or issues displayed, everything is a success!
Edit 2
I tried to use the JQuery approach below and used this syntax - but I get the error
Uncaught TypeError: $(...).load is not a function
Syntax:
<script src="https://code.jquery.com/jquery-3.1.1.slim.js"
integrity="sha256-5i/mQ300M779N2OVDrl16lbohwXNUdzL/R2aVUXyXWA="
crossorigin="anonymous" type="text/javascript"></script>
<script type="text/javascript">
$(window).load(function(){
$.get("QueryDB.php", function(data, status){
document.getElementById("data").innerHTML = data;
});
});
</script>
Edit 3
This is my php syntax that runs the sql syntax and echo result that I want to have returned from the javascript
<?php
$option = array();
$option['driver'] = 'mssql';
$option['host'] = 'host';
$option['user'] = 'user';
$option['password'] = 'password';
$option['database'] = 'database';
$option['prefix'] = '';
$db = JDatabase::getInstance( $option );
$result = $db->getQuery(true);
$result->select($db->quoteName(array('trackandfieldresults')));
$result->from($db->quoteName('[TrackData]'));
$db->setQuery($result);
$row = $db->loadRowList();
echo $row['0']
?>

Use xhr.send();
If it is a GET request, you have to apply the query string in in xhr.open and you dont have to set Content-type:application/x-www-form-urlencoded

first, the scripts should be inside the HTML before the ending body tag. then you open another file and write your code in it. JQUERY does not have script tag. Sp you are creating an external javascript file for the script. No script tag needed. Now use this format.
$(window).on('load', function(e){
e.preventDefault();
var dat = //the content you are trying to load
$.get('middleware.php', dat, function(data){
$('#selector').html(data)
});
})

I have a faster approach using JQuery.
$(window).load(function(){
$.get("QueryDB.php", function(data, status){
//Do whatever you want here
});
});
This should do the Job. Your approach is old and kind of complicated to debug

Try this
function boostion(){
var xhr;
if (window.XMLHttpRequest) {
xhr = new XMLHttpRequest();
}
else if (window.ActiveXObject) {
xhr = new ActiveXObject("Microsoft.XMLHTTP");
}
xhr.open("GET", "QueryDB.php", true);
xhr.send();
xhr.onreadystatechange = function(){
console.log(xhr);
if (xhr.readyState == 4 && xhr.status==200) {
document.getElementById("data").innerHTML = xhr.responseText;
}
}
}
<div id="data"></div>
<button onclick="boostion();">Load</button>

Data not getting passed via Ajax to PHP script

I'm trying to send the value of a variable number via ajax to a PHP script. But the PHP script is not printing the desired output on opening on a browser. Tried but couldn't find whats wrong here.
Any pointers ?
index.html
<button type="submit" class="btn btn-success" id = 'first' onclick='process();'>Submit</button>
<script>
var number = 0;
function process()
{
number++;
var xhr;
if (window.XMLHttpRequest) {
xhr = new XMLHttpRequest();
} else if (window.ActiveXObject) {
xhr = new ActiveXObject("Microsoft.XMLHTTP");
}
var data = "num=" + number;
xhr.open("POST", "index.php", true);
xhr.send(data);
}
</script>
index.php
<?php
session_start();
$number = $_POST['num'];
$_SESSION['numb'] = $number;
echo $_SESSION['numb'] ;
?>

Editing my long winded lame answer since you fixed the close curly bracket... but bloodyKnuckles is right you also need something in your 'process' function to take the response from your PHP page and output it... or whatever you want to do. You can basically use the method 'onreadystatechange' in the XMLHttpRequest object and then look for a 'readyState' property value of 4 which means everything is done. Here is a simple example of that just outputting the results to the console (which you can view using developer tools in your browser of choice).
<script>
var number = 0;
function process()
{
number++;
var xhr;
if (window.XMLHttpRequest) {
xhr = new XMLHttpRequest();
} else if (window.ActiveXObject) {
xhr = new ActiveXObject("Microsoft.XMLHTTP");
}
var data = "num=" + number;
xhr.onreadystatechange = function(){
if (xhr.readyState==4 && xhr.status==200){
console.log('xhr.readyState=',xhr.readyState);
console.log('xhr.status=',xhr.status);
console.log('response=',xhr.responseText);
}
else if (xhr.readyState == 1 ){
xhr.send(data)
}
};
xhr.open("POST", "ajax-test.php", true);
}
</script>
As you go further you may want to update your PHP page to only update the session when the POST value is there.
<?php
//ini_set('display_errors',1);
//ini_set('display_startup_errors',1);
//error_reporting(-1);
if(isset($_POST['num'])){
session_start();
$_SESSION['numb'] = $_POST['num'];
echo $_SESSION['numb'];
}
?>
You can uncomment those ini_set and error_reporting lines to try to figure out what is going on with your PHP script.

This is because you are not sending header information with request...
Append this code
xhr.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
xhr.setRequestHeader("Content-length", data.length);
xhr.setRequestHeader("Connection", "close");
after
xhr.open("POST", "index.php", true);

add javascript get function to a href

I am very new to this
I have this link:
<a onclick = sendRequest('GET','room_chart.jsp') href=#>Show Chart</a>
but I need to generate dynamic address inside that link.
I created javascript:
<script language="javascript">
var selectedOption;
var ROOM;
var BUILDING;
function GetLink(){
selectedOption = document.getElementById("roomandbuildingid").options[e.selectedIndex].text; //getting selected option
ROOM = selectedOption.split("|")[0].trim().split(":")[1].trim(); //parsing text
BUILDING = selectedOption.split("|")[1].trim().split(":")[1].trim(); //parsing text
return "'room_chart.jsp?room="+ROOM+"&building="+ BUILDING+"'"; //returning url
}
</script>
but when I paste the function into it- it does not work!
<a onclick = sendRequest('GET',GetLink()) href=#>Show Chart</a>
Now, after debug, I found out that actually it creates the proper srting, but somehow my function is not willing to accept it as URL! It is quite a paradox- it creates correct string- if I hardcode it into the code- it works! But dynamic links from variables - don't work!
please help!
see below:
my js file:
function createRequestObject(){
var req;
if(window.XMLHttpRequest){
//For Firefox, Safari, Opera
req = new XMLHttpRequest();
}
else if(window.ActiveXObject){
//For IE 5+
req = new ActiveXObject("Microsoft.XMLHTTP");
}
else{
//Error for an old browser
alert('Your browser is not IE 5 or higher, or Firefox or Safari or Opera');
}
return req;
}
//Make the XMLHttpRequest Object
var http = createRequestObject();
function sendRequest(method, url){
if(method == "get" || method == "GET"){
http.open(method,url);
http.onreadystatechange = handleResponse;
http.send(null);
// alert( document.URL );
// document.write (GetLink());
}
}
function handleResponse(){
if(http.readyState == 4 && http.status == 200){
var response = http.responseText;
if(response){
document.getElementById("ajax_res").innerHTML = response;
}
}
}

OK, the function was returning everything correctly, the parsing was not done right. I fixed it. JavaScript is hard for me to debug.