How to use stringByAddingPercentEncodingWithAllowedCharacters() for a URL in Swift 2.0

I was using this, in Swift 1.2

let urlwithPercentEscapes = myurlstring.stringByAddingPercentEscapesUsingEncoding(NSUTF8StringEncoding)

This now gives me a warning asking me to use

stringByAddingPercentEncodingWithAllowedCharacters

I need to use a NSCharacterSet as an argument, but there are so many and I cannot determine what one will give me the same outcome as the previously used method.

An example URL I want to use will be like this

http://www.mapquestapi.com/geocoding/v1/batch?key=YOUR_KEY_HERE&callback=renderBatch&location=Pottsville,PA&location=Red Lion&location=19036&location=1090 N Charlotte St, Lancaster, PA

The URL Character Set for encoding seems to contain sets the trim my URL. i.e,

The path component of a URL is the component immediately following the host component (if present). It ends wherever the query or fragment component begins. For example, in the URL http://www.example.com/index.php?key1=value1, the path component is /index.php.

However I don't want to trim any aspect of it. When I used my String, for example myurlstring it would fail.

But when used the following, then there were no issues. It encoded the string with some magic and I could get my URL data.

let urlwithPercentEscapes = myurlstring.stringByAddingPercentEscapesUsingEncoding(NSUTF8StringEncoding)

As it

Returns a representation of the String using a given encoding to determine the percent escapes necessary to convert the String into a legal URL string

Thanks

For the given URL string the equivalent to

let urlwithPercentEscapes = myurlstring.stringByAddingPercentEscapesUsingEncoding(NSUTF8StringEncoding)

is the character set URLQueryAllowedCharacterSet

let urlwithPercentEscapes = myurlstring.stringByAddingPercentEncodingWithAllowedCharacters( NSCharacterSet.URLQueryAllowedCharacterSet())

Swift 3:

let urlwithPercentEscapes = myurlstring.addingPercentEncoding( withAllowedCharacters: .urlQueryAllowed)

It encodes everything after the question mark in the URL string.

Since the method stringByAddingPercentEncodingWithAllowedCharacters can return nil, use optional bindings as suggested in the answer of Leo Dabus.

It will depend on your url. If your url is a path you can use the character set urlPathAllowed

let myFileString = "My File.txt"
if let urlwithPercentEscapes = myFileString.addingPercentEncoding(withAllowedCharacters: .urlPathAllowed) {
    print(urlwithPercentEscapes)  // "My%20File.txt"
}

Creating a Character Set for URL Encoding

urlFragmentAllowed

urlHostAllowed

urlPasswordAllowed

urlQueryAllowed

urlUserAllowed

You can create also your own url character set:

let myUrlString = "http://www.mapquestapi.com/geocoding/v1/batch?key=YOUR_KEY_HERE&callback=renderBatch&location=Pottsville,PA&location=Red Lion&location=19036&location=1090 N Charlotte St, Lancaster, PA"

let urlSet = CharacterSet.urlFragmentAllowed
                .union(.urlHostAllowed)
                .union(.urlPasswordAllowed)
                .union(.urlQueryAllowed)
                .union(.urlUserAllowed)

extension CharacterSet {
    static let urlAllowed = CharacterSet.urlFragmentAllowed
                                        .union(.urlHostAllowed)
                                        .union(.urlPasswordAllowed)
                                        .union(.urlQueryAllowed)
                                        .union(.urlUserAllowed)
}

if let urlwithPercentEscapes = myUrlString.addingPercentEncoding(withAllowedCharacters: .urlAllowed) {
    print(urlwithPercentEscapes)  // "http://www.mapquestapi.com/geocoding/v1/batch?key=YOUR_KEY_HERE&callback=renderBatch&location=Pottsville,PA&location=Red%20Lion&location=19036&location=1090%20N%20Charlotte%20St,%20Lancaster,%20PA"
}

Another option is to use URLComponents to properly create your url