Status code 0

[Leander]

Hi,

I'm trying to get some data through a PHP file in AJAX. It works
really fine, but only on Desktop. When i go mobile (iPhone 4, Android)
it doesnt work. I've got a status = 0 back and my responseText is
empty.

It goes about the following code (with a callback).

function loadXML(method, url, onsuccess)
                        {

                        var xmlhttp;

                                if (window.XMLHttpRequest)
                                { // code for IE7+, Firefox, Chrome, Opera, Safari
                                  xmlhttp = new XMLHttpRequest();
                                }
                                else
                                { // code for IE6, IE5
                                  xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
                                }

                            xmlhttp.onreadystatechange = function()
                            {
                                if (xmlhttp.readyState == 4  && xmlhttp.status == 200) {
                                                onsuccess(xmlhttp.responseText);
                                        }

                                        if(xmlhttp.readyState == 4  && xmlhttp.status == 0)
                                        {
                                                onsuccess(xmlhttp.responseText);
                                        }
                            }

                                        xmlhttp.open(method, url, true);
                                        xmlhttp.send(null);

                        }

                        function initialize() {

                                loadXML("GET", "http://example.com/testing.php",
function(location) {
                                        //Here is the variabele
location empty (only on Android/iPhone).
                                });
                       }

When i test my script on a browser, it gives me the right data back.
On Android/iPhone, it gives nothing back. Knows anybody the problem
and how i can solved it?

[Kor]

There something wrong within this part. There's a mess:

function initialize() {

                                loadXML("GET", "http://example.com/testing.php",
function(location) {
                                        //Here is the variabele
location empty (only on Android/iPhone).
                                });
                       }

It is not very clear where the functions start and end...

[Leander]

Maybe this version is better?

function loadXML(method, url, onsuccess)
{
     var xmlhttp;
          if (window.XMLHttpRequest)
          { // code for IE7+, Firefox, Chrome, Opera, Safari
                  xmlhttp = new XMLHttpRequest();
          }
          else
          { // code for IE6, IE5
                  xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
          }

          xmlhttp.onreadystatechange = function()
          {
                  if (xmlhttp.readyState == 4  && xmlhttp.status == 200) {
                       onsuccess(xmlhttp.responseText);
                  }

                  if(xmlhttp.readyState == 4  && xmlhttp.status == 0)
                  {
                       onsuccess(xmlhttp.responseText);
                  }
          }

          xmlhttp.open(method, url, true);
          xmlhttp.send(null);

}

function initialize() {
         loadXML("GET", "http://example.com/testing.php", function(location) {
              //Here is the variabele location empty (only on Android/iPhone).
         });
}

[Kor]

Why so intricate? Wouldn't be easier something like this:

function loadXML(method, url){
//...
if (xmlhttp.readyState == 4  && xmlhttp.status == 200) {
return xmlhttp.responseText);
}
//...
}

function initialize() {
var location= loadXML("GET", "http://example.com/testing.php");
// do whichever with location
}

[Leander]

Because of this function:

xmlhttp.onreadystatechange = function()
          {
                  if (xmlhttp.readyState == 4  && xmlhttp.status == 200) {
                       onsuccess(xmlhttp.responseText);
                  }

                  if(xmlhttp.readyState == 4  && xmlhttp.status == 0)
                  {
                       onsuccess(xmlhttp.responseText);
                  }
          }

If i do a return, it would never come out the xmlhttp.onreadystatechange? That's why i'm using a callback function.

[Kor]

status ==0? that means you are ready to work locally, if it is the case? If so, have you tried that?:

xmlhttp.onreadystatechange = function()
          {
                  if (xmlhttp.readyState == 4  && (xmlhttp.status == 200||xmlhttp.status == 0)) {
                       onsuccess(xmlhttp.responseText);
                  }
                  
          }

[Leander]

Yes, i have tried that!

The only problem is that i'm not working locally. I get that status code on my Android phone / iPhone 4.0.

And if i do that. The xmlhttp.responseText is empty on my Android / iPhone 4.0

Do you know what's wrong with it? I have searched already the whole web.

[Kor]

Is it the url written correct? If you write it as an absolute URL (like http://www.etc) it won't work. Is it a relative path there?

[Leander]

Is it the url written correct? If you write it as an absolute URL (like http://www.etc) it won't work. Is it a relative path there?

That was the solution Thx!

[Leander]

Thx, the problem has been solved!

[Kor]

Thx, the problem has been solved!

And the reason was? Please share the solution with us. To make us avoid a possible error, for the future

[Kor]

OK. The reason is simple: servers do often presume that a request to an absolute URL is a request to another domain, which is impossible without using a third, server-side, code (a proxy). the response status=0 usually cover that case.

[saykul.90]

would u plz specify wat relative link means?
i have specified the url as http://ip addressortno/the web service name
the web service is located on anoder machine so i have to specify the ip address