Request["key"] vs Request.Params["key"] vs Request.QueryString["key"]

Solution 1:

I recommend Request.QueryString["key"]. There isn't a lot of difference to Request["Key"] for a query string but there is a big(er) difference if you are trying to get the value from ServerVariables. Request["Key"] looks for a value in QueryString if null, it looks at Form, then Cookie and finally ServerVariables.

Using Params is the most costly. The first request to params creates a new NameValueCollection and adds each of the QueryString, Form, Cookie and ServerVariables to this collection. For the second request on it is more performant than Request["Key"].

Having said that the performance difference for a couple of keys is fairly negligable. The key here is code should show intent and using Request.QueryString makes it clear what your intent is.

Solution 2:

I prefer to use Request.QueryString["key"] because it helps the code-reader know exactly where you are getting the data from. I tend not to use Request.Params["key"] because it could refer to a cookie, query string and a few other things; so the user has to think a little. The less time someone needs to figure out what you are thinking, the easier it is to maintain the code.