小编lte*_*ech的帖子

我日复一日地熟悉C#,我遇到了这段代码

public static void CopyStreamToStream(
Stream source, Stream destination, 
Action<Stream,Stream,Exception> completed) {
byte[] buffer = new byte[0x1000];
AsyncOperation asyncOp = AsyncOperationManager.CreateOperation(null);

Action<Exception> done = e => {
    if (completed != null) asyncOp.Post(delegate { 
        completed(source, destination, e); }, null);
};

AsyncCallback rc = null;
rc = readResult => {
    try {
        int read = source.EndRead(readResult);
        if (read > 0) {
            destination.BeginWrite(buffer, 0, read, writeResult => {
                try {
                    destination.EndWrite(writeResult);
                    source.BeginRead(
                        buffer, 0, buffer.Length, rc, null);
                }
                catch (Exception exc) { done(exc); …