private void SendToChannel(string channelName, string message)
{
Validate.That(channelName).IsNotNullOrEmpty();
Validate.That(message).IsNotNullOrEmpty();
// create a DataGram instance, and ensure memory is freed
using (var dataGram = new WinMsgDataGram(channelName, message))
{
// Allocate the DataGram to a memory address contained in COPYDATASTRUCT
Native.COPYDATASTRUCT dataStruct = dataGram.ToStruct();
// Use a filter with the EnumWindows class to get a list of windows containing
// a property name that matches the destination channel. These are the listening
// applications.
var filter = new WindowEnumFilter(MessageListener.GetChannelKey(channelName));
var winEnum = new WindowsEnum(filter.WindowFilterHandler);
foreach (var hWnd in winEnum.Enumerate())
{
IntPtr outPtr;
// For each listening window, send the message data. Return if hang or unresponsive within 1 sec.
Native.SendMessageTimeout(hWnd, Native.WM_COPYDATA, IntPtr.Zero, ref dataStruct,
Native.SendMessageTimeoutFlags.SMTO_ABORTIFHUNG, 1000, out outPtr);
}
}
}
/// <summary>
/// The native window message filter used to catch our custom WM_COPYDATA
/// messages containing cross AppDomain messages. All other messages are ignored.
/// </summary>
/// <param name = "msg">A representation of the native Windows Message.</param>
protected override void WndProc(ref Message msg)
{
base.WndProc(ref msg);
if (msg.Msg != Native.WM_COPYDATA)
{
return;
}
// we can free any unmanaged resources immediately in the dispose, managed channel and message
// data will still be retained in the object passed to the event
using (var dataGram = WinMsgDataGram.FromPointer(msg.LParam))
{
if (MessageReceived != null && dataGram.IsValid)
{
MessageReceived.Invoke(this, new MessageEventArgs(dataGram));
}
}
}