Question

I’m writing a piece of code that checks if what you write in a text-box is a valid username, using jQuery and Ajax I then see if this page exists – http://api.twitter.com/1/users/show/value.xml – if it doesn’t exist i write something like “This twitter account does not exist”.

This is the code:

function checkname (name) {
 $.ajax({
 url: "http://api.twitter.com/1/users/show/" + name + ".xml",
 statusCode: {
 404: function() {
 $("#divOfInterest").html("Sorry, " + name + " is not a valid twitter account");}
 }
 });
}

But it doesn’t work and i don’t really know why, here’s my fiddle, so you can see yourself. Any help is appreciated.

Answer 1

You can create a php page on your server and make the request to the api using their method.

https://dev.twitter.com/docs/api/1/get/users/lookup

PHP page: (check.php)

if (isset($_POST['name'])) {
    $url = "https://api.twitter.com/1/users/lookup.json?screen_name=" . $_POST['name'];
    $content = @file_get_contents($url);

    if (($json_data = json_decode($content, 1)) == NULL) {
        echo 0;
    } else {
        //print_r($json_data);
        if (!empty($json_data[0]['screen_name'])) {
            // user exists
            echo 1;
        }   
    }

    exit;
}

Then call it from ajax

<script type="text/javascript">
var dataString = 'name=<?php echo $_GET['name'];?>';
$.ajax({
    type: "POST",
    url: "check.php",
    data: dataString,
    cache: false,
    datatype: 'html',
    success: function(data){
    if (data == '1') {
        alert('user exists');
    } else {
        alert('user does not exist');
    }
    //alert(result);    
    }
});
</script>

To make a request to the same page modify it this way.

put php script at the top of your document before everything else.

if (isset($_POST['ajax']) && isset($_POST['name'])) {

    PHP code

    exit; // <---- this is very important
}

in the javascript add new variable ajax=1

var dataString = 'name=<?php echo $_GET['name'];?>&ajax=1';

and the url

url: "currentpage.php",