title: URL string escape representation in objective-c? ("percent encoding")
body: <p>I want to make a very simple task in objective-c under <strong>IOS5</strong>: convert URL string to its escaped representation.</p>
  
  <p>I tried a lot of ways to do it but neither seemed to work.</p>
  
  <p>I can not make stringByAddingPercentEscapesUsingEncoding: NSASCIIStringEncoding work. It converts letters like áíűőüöúóé but does not convert others like =.</p>
  
  <p>I'd like to have a function like Uri.EscapeDataString ( <a href="http://msdn.microsoft.com/en-us/library/system.uri.escapedatastring.aspx" rel="nofollow">http://msdn.microsoft.com/en-us/library/system.uri.escapedatastring.aspx</a> ) in .net. </p>
  
  <p>Thanks!</p>