Request.QueryString没有返回正确的值

Question

I'm using AES encryption for the values of a URL. I've sampled it here with only one parameter to demonstrate the problem:

http://localhost:12345/pagename?id=ha3bEv8A%2ffs0goPGeO6NPQ%3d%3d

Request.QueryString["id"] returns "ha3bev8a/fs0gopgeo6npq==" which clearly does not match the value of the encrypted ID. Is something tripping up QueryString?

Answer 1

You are getting a URL-encoded query string, which Request.QueryString["id"] seems to decode for you. You could always just re-encode it:

string decodedId = Request.QueryString["id"];
string reEncodedId = HttpUtility.UrlEncode(decodedId);

Answer 2

The value you are seeing is in fact correct. What might be confusing you, is in the way it is presented. The id value in the URL is encoded in URL Encoding. Some characters have to be encoded in the URL String in a different way, as they are special characters that sometimes can mess up the way the string is interpreted if they aren't encoded properly.

For example, in the query string you provided: http://localhost:12345/pagename?id=ha3bEv8A%2ffs0goPGeO6NPQ%3d%3d

The %2f characters are a way to encode the '/' character, while %3d is a way to encode the '=' character.

When you get the value by getting Request.QueryString["id"] , it is decoding it back from an URL Encoded string to raw text.

Check this page for more reference. https://www.w3schools.com/tags/ref_urlencode.asp