A simple ajax system not working for me

stockton · April 29, 2009

The following very simple scenario is not working for me.

Please help.

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"
        "http://www.w3.org/TR/REC-html40/loose.dtd">
<html>
<title>Test PHP Semaphore</title>
<meta name="author" content="Alf Stockton">
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="Mon, 22 Jul 2000 11:12:01 GMT">
<script language="JavaScript" type="text/javascript" src="js/Diva.js"></script>
</head>
<body>
<center>
<h2>Test PHP Semaphore</h2>
</center>
<form action="semaphoreTest.php" method="get" name="SemaphoreTest" id="SemaphoreTest" onSubmit='return false;' >
<center>
<input type=hidden name="submit1" id="submit1" value="<?php echo $Ding; ?>" >
<P>
<input type=submit value="Submit" onclick="submit_click()">
</p>
<div id="Boodskap";></div>
<!-- <input type=text readonly name="Boodskap" id="Boodskap" value ='<?php echo $Message ?>'>; -->
</center>
</FORM>
</body>
</html>
<script language=javascript>
function submit_click()
{
alert "submit_click()";
var bError = false;
var strErrorMsg = "";
var Command = "semaphoreTest.php";
progExe(Command);
return false;
}

the semaphoreTest.php looks like:-

<?php
        {
        $intKey = GUUIDtoInt('b6379c52-d96d-418b-83c3-8aedb5e6cf95');
//        echo "Testing semaphore code<br/>";
        if (!$sem_id = sem_get($intKey)) 
            {
            $Message="\nX\n\nCould not get ID for the semaphore.";
            echo $Message;
            exit;
            } 
        else 
            {
            $Message="\nX\n\nGot semaphore ID; acquiring...";
            flush();
            if (!sem_acquire($sem_id)) 
                {
                $Message.=" failed.";
                echo $Message;
                exit;
                } 
            else 
                {
                $Message="\nX\n\nOK got it. Sleeping for 20 seconds, then releasing.";
                flush();
                sleep(20);
                sem_release($sem_id);
                $Message.="Semaphore released. Other scripts should be able to get it now.";i
                echo $Message;
                exit;
                }
            }
        }
?>

and the Diva.js is:-

function getXMLHttpRequest ()
    {
    try { return new ActiveXObject("Msxml2.XMLHTTP"); } catch(e) {};
    try { return new ActiveXObject("Microsoft.XMLHTTP"); } catch(e) {};
    try { return new XMLHttpRequest(); } catch(e) {};
    return null;
    }

// Make the XMLHttpRequest object
    var xhr = getXMLHttpRequest();

function progExe(CommandString)
    {
    xhr.open("GET", CommandString, true);
    xhr.onreadystatechange = ServerResponse;
    xhr.send(null); 
    }

function ServerResponse()
    {
    alert("entered ServerResponse()");
/* The full list of the readyState values is as follows:
    * 0 (uninitialized)
    * 1 (loading)
    * 2 (loaded)
    * 3 (interactive)
    * 4 (complete) 
*/
    if(xhr.readyState == 0)
        {
        document.getElementById("Boodskap").innerHTML = "Uninitialized........";
        }
        else
    if(xhr.readyState == 1)
        {
        document.getElementById("Boodskap").innerHTML = "Loading........";
        }
        else
    if(xhr.readyState == 2)
        {
        document.getElementById("Boodskap").innerHTML = "Loaded........";
        }
        else
    if(xhr.readyState == 3)
        {
        document.getElementById("Boodskap").innerHTML = "Interactive........";
        }
        else
    if(xhr.readyState == 4)
        {
        if (xhr.status == 200)
            {
            var parts = xhr.responseText.split("\n");
            if (parts[1] == "X")
               {
               alert(parts[3]);
               }
            else window.location=parts[3];
            document.getElementById("Boodskap").innerHTML = "";
            }
        }
    }

Ken2k7 · April 29, 2009

Define not working. Which part is failing? Or what's not working?

stockton · April 30, 2009

Theoretically I should see messages pop up in the HTML page but nothing occurs.

Ken2k7 · April 30, 2009

function ServerResponse()
    {
    alert("entered ServerResponse()");
/* The full list of the readyState values is as follows:
    * 0 (uninitialized)
    * 1 (loading)
    * 2 (loaded)
    * 3 (interactive)
    * 4 (complete)
*/
    if(xhr.readyState == 0)
        {
        document.getElementById("Boodskap").innerHTML = "Uninitialized........";
        }
        else
    if(xhr.readyState == 1)
        {
        document.getElementById("Boodskap").innerHTML = "Loading........";
        }
        else
    if(xhr.readyState == 2)
        {
        document.getElementById("Boodskap").innerHTML = "Loaded........";
        }
        else
    if(xhr.readyState == 3)
        {
        document.getElementById("Boodskap").innerHTML = "Interactive........";
        }
        else
    if(xhr.readyState == 4)
        {
        if (xhr.status == 200)
            {
            var parts = xhr.responseText.split("\n");
            if (parts[1] == "X")
               {
               alert(parts[3]);
               }
            else window.location=parts[3];
            document.getElementById("Boodskap").innerHTML = "";
            }
        }
    }

Question - does the first alert in that function work?

stockton · April 30, 2009

No it does not.

Ken2k7 · April 30, 2009

Instead of assigning onreadystatechange to ServerResponse, what if you dynamically create the function there?

xhr.onreadystatechange = function() {
   // put ServerResponse code here
}

Would that work? Did you get the alert from submit_click function?

stockton · April 30, 2009

Still nothing. Not even an alert from the submit_click() javascript function.

Ken2k7 · April 30, 2009

Try with this:

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"
        "http://www.w3.org/TR/REC-html40/loose.dtd">
<html>
<title>Test PHP Semaphore</title>
<meta name="author" content="Alf Stockton">
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="Mon, 22 Jul 2000 11:12:01 GMT">
<script language="JavaScript" type="text/javascript" src="js/Diva.js"></script>
</head>
<body>
<center>
<h2>Test PHP Semaphore</h2>
</center>
<form action="semaphoreTest.php" method="get" name="SemaphoreTest" id="SemaphoreTest" onSubmit="return submit_click();">
<center>
<input type=hidden name="submit1" id="submit1" value="<?php echo $Ding; ?>" >
<P>
<input type=submit value="Submit">
</p>
<div id="Boodskap";></div>
<!-- <input type=text readonly name="Boodskap" id="Boodskap" value ='<?php echo $Message ?>'>; -->
</center>
</FORM>
</body>
</html>
<script type="text/javascript">
function submit_click()
{
alert("submit_click()");
var bError = false;
var strErrorMsg = "";
var Command = "semaphoreTest.php";
progExe(Command);
return false;
}
</script>

stockton · April 30, 2009

I have removed the " onSubmit='return false; " from the form definition in the html and now I get the final message but not those messages inbetween.

The form definition now looks like:-

<form action="semaphoreTest.php" method="get" name="SemaphoreTest" id="SemaphoreTest" >

The messages I am also expecting but not getting are:-

"Uninitialized........"

"Loading........"

"Loaded........" and

"Interactive........" from the Diva.js script.

BTW You can actually see the programs/scripts in action at http://www.stockton.co.za/semaphoreTest.html

Ken2k7 · April 30, 2009

Sorry, I meant replace all the HTML you have with the one I posted. I thought it was implicit. I guess not.

stockton · April 30, 2009

OK I missed your implied replace and have now done that and am getting the results I wanted. Thank you.

Sign In

A simple ajax system not working for me

Recommended Posts

stockton

Link to comment

Share on other sites

Ken2k7

Link to comment

Share on other sites

stockton

Link to comment

Share on other sites

Ken2k7

Link to comment

Share on other sites

stockton

Link to comment

Share on other sites

Ken2k7

Link to comment

Share on other sites

stockton

Link to comment

Share on other sites

Ken2k7

Link to comment

Share on other sites

stockton

Link to comment

Share on other sites

Ken2k7

Link to comment

Share on other sites

stockton

Link to comment

Share on other sites

Join the conversation

Browse

Activity

Important Information