JavaScript function not responsive

Question

Hello,

I have the following code, which is the core part of my small AJAX application. I am not getting any errors, it is just that nothing happens. I am guessing there is a more efficient way to do what I am trying to do.

Here is the code:

var xmlHttp

var layername

function update(layer, part, pk, query)

{

if (part=="1")

{

$url  "get_auction.php?cmd=GetAuctionData&pk="+pk+"&sid="+Math.random()

}

else if (part=="2")

{

var url  "get_records.php?cmd=GetRecordSet&query="+query+"&sid="+Math.random()

}

xmlHttp=GetXmlHttpObject()

if(xmlHttp==null)

{

alert("Your browser is not supported?")

}



xmlHttp.onreadystatechange = function() {

        if(xmlHttp.readyState==4 || xmlHttp.readyState=="complete") {

            document.getElementById(layer).innerHTML=xmlHttp.responseText

        } else if (xmlHttp.readyState==1 || xmlHttp.readyState=="loading") {

            document.getElementById(layer).innerHTML="loading"

        }

    };

xmlHttp.open("GET",url,true)

xmlHttp.send(null)

}

function GetXmlHttpObject()

{

    var xmlHttp=null;

    try

    {

        xmlHttp=new XMLHttpRequest();

    }catch (e)

    {



        try

        {

                xmlHttp =new ActiveXObject("Microsoft.XMLHTTP");

        } 

        catch (e) {}



    }

return xmlHttp;

}

function makewindows(){

child1 = window.open ("about:blank");

child1.document.write(json_encode(<?php echo $row2["ARTICLE_DESC"]; ?>));

child1.document.close(); 

}

and an example of how I am calling the function from php

onclick="update(\'Layer3\',\'2\','.$pk.'\',\'0\',)">'

pk or query will never be passed at the same time, only one of them will ever be passed.

edit: I am also wondering if it would make more sense for the makewindows function to take a parameter, or stay as it is. Are there advantages and disadvantages for each approach?

Answer 1

I'd check the HTML the PHP is generating. Assuming $pk is a string it looks like you're missing an opening quote. Try this:

onclick="update(\'Layer3\',\'2\',\''.$pk.'\',\'0\',)">

Answer 2

json_encode is a PHP function, and thus you need to modify that particular line like so:

child1.document.write(<?php echo json_encode($row2["ARTICLE_DESC"]); ?>);

Answer 3

Looks like you may have some javascript errors:

if (part=="1")
{
   $url  "get_auction.php?cmd=GetAuctionData&pk="+pk+"&sid="+Math.random()
}
else if (part=="2")
{
   var url  "get_records.php?cmd=GetRecordSet&query="+query+"&sid="+Math.random()
}

Use Firefox and Open the javascript console to get the javascript errors, then try to fix the lines it complains about.

Javascript will stop running as soon as it encounters an error.

Also, checkout firebug if you haven't already. Great tool!