WebClient.DownloadFile-无效的URI：无法解析主机名

Question

So I tried this in several different formats and produced different results. I will include all relevant information below.

My company uses a web-based application to schedule the generation of reports. The service emails a URL that can be clicked on and will immediately begin the "Open Save As Cancel" dialogue box. I am trying to automate the process of downloading these reports with a C# script as part of a Visual Studio project (the end goal is to import these reports in SQL Server).

I am encountering terrible difficulty initiating the download of this file using WebClient Here is the closest I have gotten with any of the methods I have tried:

*NOTE: I removed all identifying information from the URL, but left all special characters and the basic architecture intact. Hopefully this will be a happy medium between protecting confidential info and giving you enough to understand my dilemma. The URL does work when manually copied and pasted into the address bar of internet explorer.

Error Message:

"Invalid URI: The hostname could not be parsed."

public void Main()
{
using (var wc = new System.Net.WebClient())
{
wc.DownloadFile(
new Uri(@"http:\\webapp.locality.company.com\scripts\rds\cgigetf.exe?job_id=3058352&file_id=1&format=TAB\report.tab"), 
@"\\server\directory\folder1\folder2\folder3\...\...\...\rawfile.tab");
        }
   }

Note also that I have tried to set:

        string sourceUri = @"http:\\webapp.locality.company.com\scripts\rds\cgigetf.exe?job_id=3058352&file_id=1&format=TAB\report.tab\abc123_3058352.tab";
        Uri uriPath;
        Uri.TryCreate(sourceUri, UriKind.Absolute, out uriPath);

But uriPath remains null - TryCreate fails.

I have attempted doing a webrequest / webresponse / WebStream, but it still cannot find the host.

I have tried including the download URL (as in my first code example) and the download URL + the file name (as in my second code example). I do not need the file name in the URL to initiate the download if I do it manually. I have also tried replacing the "report.tab" portion of the URL with the file name, but to no avail.

Help is greatly appreciated as I have simply run out of thoughts on this one. The only idea I have left is that perhaps one of the special characters in my URL is getting in the way, but I don't know which one that would be or how to handle it properly.

Thanks in advance!

Answer 1

My first thought would be that your URI backslashes are being interpreted as escape characters, leading to a nonsense result after evaluation. I would try a quick test where each backslash is escaped as itself (ie "\\" instead of "\\" in each instance). I'm also a little puzzled as to why your URI is not using forward slashes...?

// Create an absolute Uri from a string.
Uri absoluteUri = new Uri("http://www.contoso.com/");

Ref: Uri Constructor on MSDN