How To: Prevent Timeout When Inspecting Unavailabl

问题:

We have some basic C# logic that iterates over a directory and returns the folders and files within. When run against a network share (\\server\share\folder) that is inaccessible or invalid, the code seems to 'hang' for about 30 seconds before returning back from the call.

I'd like to end up with a method that will attempt to get folders and files from the given path, but without the timeout period. In other words, to reduce or eliminate the timeout altogether.

I've tried something as simple as validating the existence of the directory ahead of time thinking that an 'unavailable' network drive would quickly return false, but that did not work as expected.

System.IO.Directory.Exists(path) //hangs 

System.IO.DirectoryInfo di = new System.IO.DirectoryInfo(path); //hangs

Any suggestions on what may help me achieve an efficient (and hopefully managed) solution?

回答1:

Place it on its own thread, if it doesn't come back in a certain amount of time, move on.

回答2:

You can use this code:

var task = new Task<bool>(() => { var fi = new FileInfo(uri.LocalPath); return fi.Exists; });
task.Start();

return task.Wait(100) && task.Result;

回答3:

Perhaps you could try pinging the server first, and only ask for the directory info if you get a response?

回答4:

See...

Faster DirectoryExists function?

...for a way of setting the execution time for Directory.Exists