2

This is an odd (to me anyway) query string problem.

I'm using a installation tool that has web serial number validation. Basically the install passes a users email and serial number to a web page (or a controller method for MVC) and that takes the query string arguments and does magic to validate the installation.

One of the arguments is the email address passed in the query string.

I recently has a user who used ‘+’ email addressing to purchase a subscription. All worked well until he went to install the product and had to get past the validation screen.

After doing some digging I found that instead of receiving ‘joe+foo@gmail.com’

The validation code receives ‘joe foo@gmail.com’

Of course the space ruins the validation attempt as his email address is now wrong.

I've spoken with the install tool company (Advanced Installer, best install tool on the planet) and they claim (and I believe them) that the email is sent correctly.

So that leaves me at how do I get the asp.net mvc querystring parser do to the right thing for that particular argument and pass the string with the '+' to the contoller method ?

It's asp.net mvc 5 if it matters.

Thanks for any help you can spare.

UPDATE

The problem is with the sending, not the reception. the plus sign ends up unencoded so it translate to a space= when it get handled by the query string parser.

So what I am looking for is a way to customize the query string parser for that particular URL (and only that URL).

The shortcut to a fix is to replace spaces with a plus sign in the email arg. Simple, but I hate that kind of hackery in my code I;d prefer to have it use a customized parser to that if I need it else where I can just plug it in any way it goes.

You can customize just about everything else in asp.net mvc so I was wondering if there was a way to do the query string pasring in some custom fashion.

DougGerard
  • 75
  • 2
  • 8

2 Answers2

6

Assuming you are calling the URL from javascript, instead of doing this:

url += "?email=" + email;

Encode the value like this:

url += "?email=" + encodeURIComponent(email);

If you are calling the URL from the server, then:

string encodedEmail = Server.UrlEncode(email);

UPDATE

If you can't change where the URL is getting called, then you don't have any other option than:

HttpUtility.UrlEncode(Request.QueryString["email"]);

or:

email = email.Replace(' ', '+');
Diego
  • 16,436
  • 26
  • 84
  • 136
  • The call to the url is from a client tool (an MSI application installer), so I don't have control over how it's called, it's the parsing as handled by asp.net mvc that I need to prevent from converting the + to a space, at least for just that url. – DougGerard Sep 11 '15 at 19:33
  • In that case, I'm not sure if you have any other option than doing `HttpUtility.UrlEncode(Request.QueryString["email"]);` or `email = email.Replace(' ', '+');` – Diego Sep 11 '15 at 19:47
  • The replace is ultimately the solution, even though I don't like it so much. Thanks for the help. – DougGerard Sep 11 '15 at 20:23
  • Yes, I know its very ugly, but I don't know any way to avoid the automatic decoding of `HttpRequest`. I'm updating my answer – Diego Sep 11 '15 at 20:28
1

It looks like I'm going to have to go with my hack solution of swapping space for a plus sign in that particular query string parameter. Not the ideal solution in my way of thinking, but it will do the trick.

DougGerard
  • 75
  • 2
  • 8