using CMS.Messaging;

using CMS.CMSHelper;

using CMS.SiteProvider;

using CMS.GlobalHelper;

...

        // Creates a new message from CurrentUser to administrator

        MessageInfo message = new MessageInfo();

        message.MessageSubject = "Subject";

        message.MessageBody = "Hello world!";

        message.MessageSenderUserID = CMSContext.CurrentUser.UserID;

        message.MessageRecipientUserID = UserInfoProvider.GetUserInfo("administrator").UserID;

        message.MessageSent = DateTime.Now;

        MessageInfoProvider.SetMessageInfo(message);

        // Gets the previously created message and edits its body

        MessageInfo messageToEdit = MessageInfoProvider.GetMessageInfo(message.MessageID);

        messageToEdit.MessageBody += " This message was edited";

        MessageInfoProvider.SetMessageInfo(messageToEdit);

        // Deletes the previously created and edited message

        MessageInfoProvider.DeleteMessageInfo(message.MessageID);