Question

I’m invoking a REST web service that performs a GET to obtain some attachment data. The parameters it takes are SRNumber, External_Id, attachmentId, and attachmentName. There are certain invoke URLs that work in the browser, but don’t work when I invoke the service through code. One in particular I’m testing has the following parameters:

• SRNumber = 1000
• ExternalId = USERID7/27/2012 10:43:00 AM
• attachmentId = 1-2H1USPQ
• attachmentName = File name goes here

Here’s the URL formatted with URL-encoded parameters:

http://baseurl/service/CHD/Service_Record_Attachment_Query/SRNumber/1000/External_Id/USERID7%2F27%2F2012%2010%3A43%3A00%20AM/attachmentId/1-2H1USPQ/attachmentName/File%20name%20goes%20here/

When I attempt to do a GET through code, though, I am receiving an error. It appears that the web service is reading the URL-encoded ‘/’ character as if it’s a delimiter in the URL (I stepped through the code to verify that when the string was built, the ‘/’ in the External_Id was URL-encoded.)

Here’s the code I’m using the build the URL String:

requestURL = ConfigurationManager.AppSettings["Server"] +
    ConfigurationManager.AppSettings["Service"] +
    "Service_Record_Attachment_Query/SRNumber/" + 
    System.Uri.EscapeDataString(SRNumber) + "/External_Id/" +
    (ExternalID.Equals(null) ? "" : System.Uri.EscapeDataString(ExternalID)) +
    "/attachmentId/" + System.Uri.EscapeDataString(AttachmentID) +
    "/attachmentName/" + System.Uri.EscapeDataString(AttachmentName) + "/";

After building the request String, I use that to create an HTTPWebRequest:

HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(requestURL);

Then I get an error back saying the attachment does not exist since it’s only searching for “USERID7” and excluding the rest of the attachment name.

Am I doing something wrong in my code that could be causing the ‘/’ character to be interpreted as a delimiter? I don’t understand why it returns a successful response when I put the invoke URL in the browser, but the same invoke URL through code returns an error.

Answer 1

Use a tool like Fiddler to look at what is actually passing across the network wire in the browser and code cases. The browser may be double-escaping the ‘/’ chars in the URL, or your code may not be escaping it the way you think it is. Looking at the HTTP request on the wire should tell you a lot.