/// <summary>
/// Copy the contents of one <see cref="Stream"/> to another.
/// </summary>
/// <param name="source">The stream to source data from.</param>
/// <param name="destination">The stream to write data to.</param>
/// <param name="buffer">The buffer to use during copying.</param>
/// <param name="progressHandler">The <see cref="ProgressHandler">progress handler delegate</see> to use.</param>
/// <param name="updateInterval">The minimum <see cref="TimeSpan"/> between progress updates.</param>
/// <param name="sender">The source for this event.</param>
/// <param name="name">The name to use with the event.</param>
/// <param name="fixedTarget">A predetermined fixed target value to use with progress updates.
/// If the value is negative the target is calculated by looking at the stream.</param>
/// <remarks>This form is specialised for use within #Zip to support events during archive operations.</remarks>
static public void Copy(Stream source, Stream destination,
byte[] buffer,
ProgressHandler progressHandler, TimeSpan updateInterval,
object sender, string name, long fixedTarget)
{
if (source == null) {
throw new ArgumentNullException("source");
}
if (destination == null) {
throw new ArgumentNullException("destination");
}
if (buffer == null) {
throw new ArgumentNullException("buffer");
}
// Ensure a reasonable size of buffer is used without being prohibitive.
if (buffer.Length < 128) {
throw new ArgumentException("Buffer is too small", "buffer");
}
if (progressHandler == null) {
throw new ArgumentNullException("progressHandler");
}
var copying = true;
var marker = DateTime.Now;
long processed = 0;
long target = 0;
if (fixedTarget >= 0) {
target = fixedTarget;
}
else if (source.CanSeek) {
target = source.Length - source.Position;
}
// Always fire 0% progress..
var args = new ProgressEventArgs(name, processed, target);
progressHandler(sender, args);
var progressFired = true;
while (copying) {
var bytesRead = source.Read(buffer, 0, buffer.Length);
if (bytesRead > 0) {
processed += bytesRead;
progressFired = false;
destination.Write(buffer, 0, bytesRead);
}
else {
destination.Flush();
copying = false;
}
if (DateTime.Now - marker > updateInterval) {
progressFired = true;
marker = DateTime.Now;
args = new ProgressEventArgs(name, processed, target);
progressHandler(sender, args);
copying = args.ContinueRunning;
}
}
if (!progressFired) {
args = new ProgressEventArgs(name, processed, target);
progressHandler(sender, args);
}
}