Handling two WebException's properly [closed]
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Closed 10 months ago.
Improve this questionI am trying to handle two different WebException
's properly.
Basically they are handled after calling WebClient.DownloadFile(string address, string fileName)
AFAIK, so far there are two I have to handle, both WebException
's:
- The remote name could not be resolved (i.e. No network connectivity to access server to download file)
- (404) File not nound (i.e. the file doesn't exist on the server)
There may be more but this is what I've found most important so far.
So how should I handle this properly, as they are both WebException
's but I want to handle each case above differently.
This is what I have so far:
try
{
using (var client = new WebClient())
{
client.DownloadFile("...");
}
}
catch(InvalidOperationException ioEx)
{
if (ioEx is WebException)
{
if (ioEx.Message.Contains("404")
{
//handle 404
}
if (ioEx.Message.Contains("remote name could not")
{
//handle file doesn't exist
}
}
}
As you can see I am checking the message to see what type of WebException
it is. I would assume there is a better or a more precise way to do this?
Based on this MSDN article, you could do something along the following lines:
try
{
// try to download file here
}
catch (WebException ex)
{
if (ex.Status == WebExceptionStatus.ProtocolError)
{
if (((HttpWebResponse)ex.Response).StatusCode == HttpStatusCode.NotFound)
{
// handle the 404 here
}
}
else if (ex.Status == WebExceptionStatus.NameResolutionFailure)
{
// handle name resolution failure
}
}
I'm not certain that WebExceptionStatus.NameResolutionFailure
is the error you are seeing, but you can examine the exception that is thrown and determine what the WebExceptionStatus
for that error is.
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