Which characters in urls cause file_get_contents / curl to fail? - php

Question

EDIT FOR CLARIFICATION:
I would like to know which characters in a url cause file_get_contents / curl to fail.
In the example below, the only character which causes a problem is the space, so the best thing for me to do would simply be to str_replace spaces in the url with %20. Are there any other characters which also cause it to fail? If so, what are they? Is there a function which does this replacement for me?
ORIGINAL PHRASING:
I'd like to be able to download an arbitrary file by its URL, chosen by the user, and have access to it as a string. My initial reaction was:
$str = file_get_contents($url);
However, this fails on URLs like:
http://i.ebayimg.com/t/2-WAY-PHOTO-FRAME-KEY-BOX-SHABBY-CHIC-STYLE-/00/s/NjAwWDYwMA==/$(KGrHqRHJDoE-PBe-SSLBPlrnIYb Q~~60_35.JPG
Next, I tried cURL:
function file_get_contents_curl($url) {
$ch = curl_init($url);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
$result = curl_exec($ch);
curl_close($ch);
return $result;
}
However, for the same URL, cURL fails with "Invalid URL".
I've read on a number of questions here that when downloading from URLs with arbitrary characters in them, urlencode must be used. However, this results in:
http%3A%2F%2Fi.ebayimg.com%2Ft%2F2-WAY-PHOTO-FRAME-KEY-BOX-SHABBY-CHIC-STYLE-%2F00%2Fs%2FNjAwWDYwMA%3D%3D%2F%24%28KGrHqRHJDoE-PBe-SSLBPlrnIYb+Q%7E%7E60_35.JPG
which doesn't fetch either, using either method, I think because now it thinks it's a local file. What do I need to do to be able to fetch an arbitrary url?

Answer 1

Try this:
$url = "http://i.ebayimg.com/t/2-WAY-PHOTO-FRAME-KEY-BOX-SHABBY-CHIC-STYLE-/00/s/NjAwWDYwMA==/$(" . urlencode("KGrHqRHJDoE-PBe-SSLBPlrnIYb Q~~60_35.JPG");
$str = file_get_contents($url);
Edit: As Galen said the only problem with URL is the space and it can be fixed using str_replace as below.
$url = "http://i.ebayimg.com/t/2-WAY-PHOTO-FRAME-KEY-BOX-SHABBY-CHIC-STYLE-/00/s/NjAwWDYwMA==/$(KGrHqRHJDoE-PBe-SSLBPlrnIYb Q~~60_35.JPG";
$url = str_replace(' ', '+', $url);
$str = file_get_contents($url);