How to invoke PHP file in AJAX/JavaScript? - php

Question

I have this code that GET the php file using an AJAX method. The goal is to inform the user if the movie table is empty or not. If the table is empty, it will display a confirm box that will ask if the user wants to add movies or not?
Here's my index.php file:
Movies
Here's my moviestbl.php:
<?php
include ('../phpfunc/connect'); //includes the connection to mysql
$checkMovieTable = mysql_query("SELECT * FROM movies ORDER BY title ASC") or die("Table not found");
$countRows = mysql_num_rows($checkMovieTable);
if($countRows == 0){
?>
<script language="JavaScript">
var option = confirm("No Movies found. Add Movies now?");
if(option ==true){
//redirect to another page
window.location = "../addmedia.php?add=movies";
}
else{
//do nothing. return to current window.
}
</script>
<?php
}
?>
And finally, here's my AJAX file.
<script>
/*connect to database then count the table, if it's zero, dispLay a confirmation box*/
var XMLHttpRequestObject = false;
if(window.XMLHttpRequest){
XMLHttpRequestObject = new XMLHttpRequest();
}
else if(window.ActiveXObject){
XMLHttpRequestObject = new ActiveXObject("Microsoft.XMLHTTP");
}
function checkMovieTable(dataSource){
//get data from the server
//onreadystatechange = stores a function
var obj = document.getElementById("readystate");
XMLHttpRequestObject.open("GET", dataSource);
XMLHttpRequestObject.onreadystatechange = function() {
if(XMLHttpRequestObject.status == 200){
obj.innerHTML = XMLHttpRequestObject.responseText;
}
}
XMLHttpRequestObject.send(null);
}
</script>
When I click the link, it is not doing or displaying anything. need help. thanks.

Answer 1

You will need to get the data from server using an ajax request , the response could be in JSON format.
Suggestions .
use jQuery and $.ajax - for pulling data from server
on getting the response - do the confirm and switch window
You can structure the logic to handle specific logics at client & server
PHP : logic on server could beCreate and interface for responding with JSON result for status of entries on movie table. your current query should work fine.
Javascript: Make use of the interface defined on php to to query data and make use of the 'confirm' javascript to do the switching.
Right now if you change
Movies
to
Movies
You should see it working with page reloads and redirects.

Answer 2

This will probably work better:
<?php
include ('../phpfunc/connect'); //includes the connection to mysql
$checkMovieTable = mysql_query("SELECT * FROM movies ORDER BY title ASC") or die("Table not found");
$countRows = mysql_num_rows($checkMovieTable);
if($countRows == 0){
echo "empty";
}
?>
<script>
/*connect to database then count the table, if it's zero, dispLay a confirmation box*/
var XMLHttpRequestObject = false;
if(window.XMLHttpRequest){
XMLHttpRequestObject = new XMLHttpRequest();
}
else if(window.ActiveXObject){
XMLHttpRequestObject = new ActiveXObject("Microsoft.XMLHTTP");
}
function checkMovieTable(dataSource){
//get data from the server
//onreadystatechange = stores a function
var obj = document.getElementById("readystate");
XMLHttpRequestObject.open("GET", dataSource);
XMLHttpRequestObject.onreadystatechange = function() {
if(XMLHttpRequestObject.status == 200){
obj.innerHTML = XMLHttpRequestObject.responseText;
if(XMLHttpRequestObject.responseText === "empty"){
var option = confirm("No Movies found. Add Movies now?");
if(option == true){
//redirect to another page
window.location = "../addmedia.php?add=movies";
} else{
//do nothing. return to current window.
}
}
}
}
XMLHttpRequestObject.send(null);
}
</script>

Answer 3

I was able to make the code run now. Thanks to Firebug and coffee. The anchor tag is the problem. I don't know why, but when I used the img instead, it worked.
<img alt="movies" style="cursor:hand;cursor:pointer;" onclick="checkMovieTbl('/movies/ajaxphp/moviestbl.php')"/>
The PHP Script file:
<?php
//fetch the data from the table movies
include '../phpfunc/connect.php';
$checkMovieTable = mysql_query("SELECT * FROM movies ORDER BY title ASC") or die("Table not found");
$countRows = mysql_num_rows($checkMovieTable);
$json = json_encode($countRows);
if($json == 0){
echo $json;
}
?>
And lastly, the AJAX file.
var XMLHttpRequestObject = false;
if (window.XMLHttpRequest) {
XMLHttpRequestObject = new XMLHttpRequest();
}
else if (window.ActiveXObject) {
XMLHttpRequestObject = new ActiveXObject("Microsoft.XMLHTTP");
}
function checkMovieTbl(url){
//if not false
if(XMLHttpRequestObject){
XMLHttpRequestObject.open("GET", url, false); //not sync
XMLHttpRequestObject.onreadystatechange = function(){
if(XMLHttpRequestObject.readyState == 4 && XMLHttpRequestObject.status == 200){
var response = XMLHttpRequestObject.responseText;
//alert(XMLHttpRequestObject.responseText + "readyState:" + XMLHttpRequestObject.readyState + "\nStatus:" +XMLHttpRequestObject.status);
if(response==0){
//execute something here
}
}
else{
alert(XMLHttpRequestObject.responseText + "readyState:" + XMLHttpRequestObject.readyState + "\nStatus:" +XMLHttpRequestObject.status);
}
}
XMLHttpRequestObject.send();
}
}
Thanks to everyone who answered my questions and helped me. Chiao!