How to recursively list all the files in a directory in C#?

Arjab picture Arjab · May 30, 2009 · Viewed 291.2k times · Source

How to recursively list all the files in a directory and child directories in C#?

Answer

Marc Gravell picture Marc Gravell · May 30, 2009

Note that in .NET 4.0 there are (supposedly) iterator-based (rather than array-based) file functions built in:

foreach (string file in Directory.EnumerateFiles(path, "*.*", SearchOption.AllDirectories))
{
    Console.WriteLine(file);
}

At the moment I'd use something like below; the inbuilt recursive method breaks too easily if you don't have access to a single sub-dir...; the Queue<string> usage avoids too much call-stack recursion, and the iterator block avoids us having a huge array.

static void Main() {
    foreach (string file in GetFiles(SOME_PATH)) {
        Console.WriteLine(file);
    }
}

static IEnumerable<string> GetFiles(string path) {
    Queue<string> queue = new Queue<string>();
    queue.Enqueue(path);
    while (queue.Count > 0) {
        path = queue.Dequeue();
        try {
            foreach (string subDir in Directory.GetDirectories(path)) {
                queue.Enqueue(subDir);
            }
        }
        catch(Exception ex) {
            Console.Error.WriteLine(ex);
        }
        string[] files = null;
        try {
            files = Directory.GetFiles(path);
        }
        catch (Exception ex) {
            Console.Error.WriteLine(ex);
        }
        if (files != null) {
            for(int i = 0 ; i < files.Length ; i++) {
                yield return files[i];
            }
        }
    }
}