The Uri gotcha that gotcha'd me good

by Peter Tyrrell Friday, October 20, 2006 1:28 PM

When working on ASP.NET web applications, it's not unusual to be working with the System.Uri class, which is an object representing a uniform resource identifier (URI). It can spit back handy references to various properties of a URL, such as host, query, scheme, yada yada.

I was down in the dingy Andornot lab today, working on the Onesearch class library and feeling clever because I was using Uri objects to hold WebPublisher search URLs instead of mere strings. But strangely, something kept going wrong whenever I called upon the Uri to actually perform a web request. The search text I was passing in was not getting encoded. (This is so "doctor & nurse" gets encoded to "doctor+%26+nurse" and doesn't make WebPublisher cry like a wet-nappied baby.)

I encoded that string every which way I knew how, and viewed the results in the trace log. It was going in encoded, but somehow whenever I asked for the whole Uri as a string to make a web request, it came out "doctor+&+nurse". I was going completely bananas. Had I slipped into some alternate Twilight Zone universe? Was there a bug in the .NET 2.0 framework? Where was my encoding? Double U Tee Eff!

I finally figured it out. I had been asking for Uri.ToString(), which indeed returns a full string representation of the Uri, sans encoding, even if you had forced encoding upon any portion of the Uri previously. Buggrit! Millenium hand and shrimp! I humbly accept my chastisement from the gods, and ask instead for Uri.AbsoluteUri(), which returns a full string with encoding. Amen.

As a postscript, UriBuilder.Query is a trip-up as well. Do not append a string directly to this property! I did, and now I'm sorry.


uriBuilder.Query += "&QI0=smith";

What does that get you? Two question marks preceding the query instead of one.


uriBuilder.Query = uriBuilder.Query.Substring(1) + "&QI0=smith";


blog comments powered by Disqus

Month List