Use jQuery to check if a URL on another domain is 404 or not?

Question

On the client side using jQuery, I want to know if I can just check if a link URL is valid (i.e. doesn't return a 404). This link points to another domain, so if I just use $.get() then I end up with a permission issue. I remember reading something about using a JSONP request, but I don't remember.

Answer 1

I found a solution that seems to work (using YQL):

$.getJSON("http://query.yahooapis.com/v1/public/yql?"+
            "q=select%20*%20from%20html%20where%20url%3D%22"+
            encodeURIComponent(url)+
            "%22&format=xml'&callback=?",
    function(data){
      if(data.results[0]){
        // do whatever
      } 
    }
  );

Assumes the URL you want to check is in the variable 'url'.