AS3 string util to convert to x-www-form-urlencoded ?

Question

Is there a library for converting strings in as3 into the application/x-www-form-urlencoded format?

Specifically, I am looking for the same functionality as the java URLEncoder http://java.sun.com/javase/6/docs/api/java/net/URLEncoder.html

Unfortunately, as3's escape and encodeURIComponent functions don't do it. For example, lots of %20s instead of +'s.

Answer 1

For encoding URL parameters, both %20 and + are valid representations of the space character, and both URLVariables.toString() and URLUtil.objectToString() emit compliant application/x-www-form-urlencoded data using the former (per ECMA-262). The encodeURI(), encodeURIComponent() and escape() functions all operate similarly. From the AS3 docs:

flash.net.URLVariables.toString()

Returns a string containing all enumerable variables, in the MIME content encoding application/x-www-form-urlencoded.

mx.utils.URLUtil.objectToString()

You typically use this method to convert an ActionScript object to a String that you then append to the end of a URL. By default, invalid URL characters are URL-encoded (converted to the %XX format).

encodeURIComponent()

Encodes a string into a valid URI component. Converts a substring of a URI into a string in which all characters are encoded as UTF-8 escape sequences unless a character belongs to a very small group of basic characters.

escape()

Converts the parameter to a string and encodes it in a URL-encoded format, where most nonalphanumeric characters are replaced with % hexadecimal sequences.

Here's an example showing the usage and output of all four approaches:

import mx.utils.URLUtil;

private function test():void
{
    var url:String = "http://www.google.com/search?";
    var s:String = "here is my search query";

    var variables:URLVariables = new URLVariables();
    variables.q = s;

    var o:Object = new Object();
    o.q = s;

    trace(url + "q=" + encodeURIComponent(s));
    trace(url + variables.toString());
    trace(url + "q=" + escape(s));
    trace(url + URLUtil.objectToString(o));
}

All four emit the same result (just as JavaScript's own encodeURIComponent() does):

// http://www.google.com/search?q=here%20is%20my%20search%20query

I agree the plus signs are easier on the eyes, though! To swap them out manually:

trace(url + "q=" + escape(s).split("%20").join("+"));

But if there's an ActionScript class or top-level function that uses plus signs instead of hex sequences for spaces, I'm not aware of it.

Answer 2

Thanks a lot! Actually spent several hours of this, when sending usernames (containing strange characters) from flex to a java REST service. encodeURIComponent on the flex side did the trick!