Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Asynchronous downloading files in C Ask Question. Asked 7 years, 1 month ago. Active 7 years, 1 month ago. Viewed 3k times. I have a question about asynchronous operations in C.
How could I do it? Improve this question. Junior Junior 3 3 gold badges 11 11 silver badges 21 21 bronze badges. Add a comment. Active Oldest Votes. If you use this modifier on a method or expression, it's referred to as an async method. The following example defines an async method named ExampleMethodAsync :.
If you're new to asynchronous programming or do not understand how an async method uses the await operator to do potentially long-running work without blocking the caller's thread, read the introduction in Asynchronous programming with async and await. The following code is found inside an async method and calls the HttpClient. GetStringAsync method:. An async method runs synchronously until it reaches its first await expression, at which point the method is suspended until the awaited task is complete.
In the meantime, control returns to the caller of the method, as the example in the next section shows. If the method that the async keyword modifies doesn't contain an await expression or statement, the method executes synchronously. A compiler warning alerts you to any async methods that don't contain await statements, because that situation might indicate an error.
Directory class, as shown below:. GetFiles rootdir ; Console. WriteLine String. Join Environment. GetDirectories rootdir ; Console. Download Code. The above-mentioned methods are overloaded to accept the search pattern and search options. If the search pattern is specified, the method matches the pattern against the names of files and directories in the path.
The search options specify whether the search should include all subdirectories or only the root directory. AllDirectories option to retrieve all types of files in the current directory and its subdirectories. Connect and share knowledge within a single location that is structured and easy to search.
Is there an asynchronous version of DirectoryInfo. GetDirectories in dotNet? I'd like to use them in an F async block, and it'd be nice to have a version that can be called with AsyncCallbacks.
Problem is I'm trying to suck in a bunch of directories, probably on SMB mounts over slow network connections, and I don't want a bunch of thread pool threads sitting around waiting for network reads when they could be doing other work. No, I don't think there is.
The pool thread approach is probably the most pragmatic. I didn't find an async version of GetFiles, however if you look at the sourcecode for other Async operations, they're defined as follows:. You can easily consume these from traditional. Actually, according to the help for Directory. GetFiles , Directory. EnumerateFiles will return the first result immediately it's an IEnumerable , rather than wait for the entire list before returning.
I believe that's probably what you're looking for. Princess's answer is the way to go for adding granularity between tasks - so this kind of thing would let other players use the thread pool:.
It doesn't help as much when each one of those blocking calls is heavy - and a GetFiles over SMB is pretty much the definition of heavy. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Is there an async version of DirectoryInfo. Ask Question. Asked 12 years, 7 months ago. Active 5 years ago.
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