AJAX & PHP

[Ioannis_o5]

Although I am not sure that I can help you the way you put the question, I will try. I use a lot of Ajax and in my opinion i. you are close to the traditional way , ii . you could find other solutions. My comments : a. Your example seems to be OK. Of course it returns whatever you havae passed as email. Pls confirm that is is so. b. Do I understand that you want to pass THE NAME of a variable and receive a value OR IS IT you want the calling javascript to decide what to do and NOT the called PHP. c. Before you clear this II would suggest : Wht don't you store your values in the php script in arrays like this $name= "Napoleon"; $myphone = "199199"; $myvalues[]=array("name" => $name , "phone" => $myphone ); $value_of_param= $_GET["req"]; // req is in place of your email variable echo $myvalues[$value_of_param]; (I hope I have no typo errors)

[Bryant May]

Hi there, thanks for getting back to me! I'll try and be a bit clearer on what im asking...So, I have an Ajax function that calls a php script which contains a variable with a value (lets say $one = 1). If I print this variable in my php script (print $one;) and output it in my Ajax function like so:

var result = XMLHttpRequestObject.responseText;
document.getElementById("div").innerHTML = result;

This will obviously output the variable value of 1 to "div". But what i actually want to do is, in my ajax function say

var result = XMLHttpRequestObject.responseText;
if (result.$one == 1)
{
somecodeHere;
}

Hopefully thats a little clearer. If you need me to explain further thats no problem. Thank you Bryant

[Ioannis_o5]

Hello again Bryant, I believe that your $one should be passed to the php page and the response must be the value of $one. This

result.$one

doent look 'nice' to me. For instance if there should be a variable in your php code called $one , if you don't follow my previous comment for an array then it could look like :

$variable_name = $_GET["req"];
if ($variable_name == "one")
echo $one;
/// etc.

This means of course that your java line that creates the URL should be like :

var url = "/cms/_sql/sendPassword.php?req=one"

and then your script (above) changes to

var result = XMLHttpRequestObject.responseText;
if (result == '1')
{ somecodeHere;
}

I ll be glad to help more if I can

[Bryant May]

hey cheers for getting back to me so quickly. Hopefully Im starting to understand this after your excellent explanation. Heres where Im getting lost.. Whats going to happen in my script is that an email address is going to be checked to make sure it is valid. If it is then I want my php script to initialise a variable which is then sent back in the responsetext object which I want to be able to access from the ajax function. It looks kind of like this:

function checkRemForm(email, div)
{

createObject();

if (XMLHttpRequestObject)
{
var url = "/cms/_sql/sendPassword.php?email=" +email.value;

XMLHttpRequestObject.open('GET', url, true);

XMLHttpRequestObject.onreadystatechange = function()
{
if (XMLHttpRequestObject.readyState == 4 && XMLHttpRequestObject.status == 200)
{
var result = XMLHttpRequestObject.responseText;
if (result == 1)
{
targetDiv.innerHTML = result;
}
else
targetDiv.innerHTML = "no";
}
}
XMLHttpRequestObject.send(null);
}

and my php, at the moment is simply

$email = $_GET['email'];
print $email;
$one = 1;

?>

In the end, the php script will run an sql statement, checking the email against a database and if its all ok the $one variable will be initialised. It is this that i want access to in my ajax script, like I have shown above. Sorry if Im being stupid about this, Ive tried everything I can think of to get at that $one!! Once again, thank you for your time and help. Bryant

[Ioannis_o5]

I ve just written this little piece of code (interrupting my VB project development - dont bother I like it) :

if (isset($_GET["email"])) // if the email var was passed
{
include('dbconn.php') // connect etc. to your mysql - i have this stuff in dbconn.php
$query="select email,blabla,etc FROM MyTable WHERE email='".$_GET["email"]."'";
$result=mysql_query($query) or die('0');
if (mysql_num_rows($result)>0) // if at least one record with this email
echo '1'; // then send 1
else
echo '0'; // else send 0
mysql_free_result($result);
}

I you have questions be back. Anyway let me know : did this help ?

[Bryant May]

Im sorry to interupt your work.....I'll continue to do it though by asking you this :) That bit of code that you added is all fine, I can do that...php is the language I am most familiar with. The problem comes when I try to access the '1' in javascript. I dont actually want to output the '1', I just want to set it. So your 'if' statement becomes: if (mysql_num_rows($result)>0) $one = 1; I then need to be able to say (in my ajax statement): (pseudo code)

if (in result $one equals 1)
{
do this;
}

Remembering that 'result' is the value of responseText. So basically, how do I access a variable value passed FROM php TO an ajax function. To say it plainly.

[Ioannis_o5]

I will disappoint you : You can't do that BUT you need not do that ! Think of the php page as a black box which can ONLY return a return string to the requesting javascript. That is : the javascript via the URL "thinks" that it requests a page from the server. The requested page (php) is executed and with the echo (or the print) statement it can send back text. This text received can be anything you like - anything the php programmer has designed. And this text is received in the

XMLHttpRequestObject.responseText

. And this responseText IS THE ONLY VIEW that you can have from you AJAX request to the php : php variables are NOT visible / accessible by the javascript. If all you want is to do your job then why do you worry. Or is it just curiosity? Send a message if there's anything else I can give a hand. I wish you good luck.

[Bryant May]

Im doing this as a project for university. This is part of a log in script for a content management system...the whole validation of an email and sending back a variable etc... As you can see Im learning Ajax and can do quite a bit with it already but im struggling to understand this bit of it. The part I dont get is that if my 'responseText' object contains my variable then why cant I get at it in any other way than outputting it to the screen. If I dont output it in my "innerText ='result';" statement then its still within result. In my mid there must be a way of accessing the contents of 'result'...Maybe not, I dont know. Anyway, thanks for your time and efforts on helping me out with this. I really appreciate it.

[Ioannis_o5]

Hello I am back again (I went to bed that's why I didn't answer this - you see I am in time zone GMT +2 ). NOW I SEE WHAT YOUR PROBLEM IS : The value you receive in responseText you DON'T HAVE TO DISPLAY IT ! For instance you can 'say' :

var result = XMLHttpRequestObject.responseText;
if (result==1)
document.getElementById(div).style.visibility='hidden';
else
// do something else

A last comment regarding your project : Things that can/must be done AT SERVER put them in the php script, while those that need the user's update and response hndle them with Java after returning from AJAX. My wishes for success. I ll check my mail again in about 6 hours. If there anything else, send a message. Cheers

[Bryant May]

The way Ive kind of got this working is to do this:

var result = XMLHttpRequestObject.responseText;

targetDiv.innerHTML = result; //Output any error messages printed in the php script

if (targetDiv.innerHTML == "") // If there arent any error messages then do this code
{
// Some code
}

Its not exactly what I want because it doesnt allow for switching based on true variables that arent errors (I cant think of an example there but Im sure you get what I mean). So I've done as you say, I've carried out all the things that the php script has to do IN the php script (outputting any errors, sql statements etc...) and used the javascript function to do everything else. Its quite untidy code-wise but it does the trick I suppose. Thank you for all your help. It has helped massively. Good luck with your VB project :) Bryant