I want to use javascript / jquery to determine if an xml file exists. I don't need to process it; I just need to know whether it's available or not,but I can't seem to find a simple check.
Here is what I've tried:
jQuery.noConflict();
jQuery(document).ready(function(){
var photo = '223';
var exists = false;
jQuery.load('/'+photo+'.xml', function (response, status, req) {
if (status == "success") {
exists = true;
}
});
});
Assuming you are talking about an xml file on the server, you could do a ajax request and then write a custom error handler to check the error response message. You'll need to know what the exact error message code is for a missing file (usually 404). You can use Firebug Console to check what the exact error message and code is.
$.ajax({
type: "GET",
url: "text.xml",
dataType: "xml",
success: function(xml) {
alert("great success");
},
error: function(xhr, status, error) {
if(xhr.status == 404)
{
alert("xml file not found");
} else {
//some other error occured, statusText will give you the error message
alert("error: " + xhr.statusText);
}
} //end error
}); //close $.ajax(
xhr.status === 404, rather than xhr.statusText == "Not Found", as status will contain a numerical error code rather than arbitrary string which may or may not even be set by the server's error handler depending on the implementer. If you really wanted to be robust you could check if(xhr.status >== 400) { alert('failed'); }.Your question isn't clear to me. If I understand, you want to verify whether a file (the XML) is present or not in the HTTP server.
That's correct? If so, you can just do:
$.get('url-to-file.xml', function(response, status, req) {
if (status == 'success') {
alert('exists');
}
});
EDITED: As pointed by @lzyy on comments, .get() only calls the callback upon success. However, I'd stick to the .load() using $(document) as selector. See:
$(document).load('url-to-file.xml', function(response, status, req) {
if (status == 'success') {
alert('exists');
} else if (status == 'error') {
alert('doesnt exist');
}
});
