add role property

HandyControlDemo/ViewModel/Basic/ChatBoxViewModel.cs

@@ -0,0 +1,83 @@
+using System;
+using System.IO;
+using System.Windows.Input;
+using GalaSoft.MvvmLight;
+using GalaSoft.MvvmLight.CommandWpf;
+using GalaSoft.MvvmLight.Messaging;
+using HandyControlDemo.Data;
+using Microsoft.Win32;
+
+namespace HandyControlDemo.ViewModel
+{
+    public class ChatBoxViewModel : ViewModelBase
+    {
+        private readonly string _id = Guid.NewGuid().ToString();
+
+        public ChatBoxViewModel()
+        {
+            Messenger.Default.Register<ChatInfoModel>(this, MessageToken.SendChatString, ReceiveString);
+            Messenger.Default.Register<ChatInfoModel>(this, MessageToken.SendChatImage, ReceiveImage);
+            Messenger.Default.Register<ChatInfoModel>(this, MessageToken.SendChatAudio, ReceiveAudio);
+        }
+
+        private void ReceiveString(ChatInfoModel info)
+        {
+            if (!_id.Equals(info.SenderId)) return;
+        }
+
+        private void ReceiveImage(ChatInfoModel info)
+        {
+            if (!_id.Equals(info.SenderId)) return;
+        }
+
+        private void ReceiveAudio(ChatInfoModel info)
+        {
+            if (!_id.Equals(info.SenderId)) return;
+        }
+
+        private string _chatString;
+
+        public string ChatString
+        {
+            get => _chatString;
+            set => Set(ref _chatString, value);
+        }
+
+        public RelayCommand<KeyEventArgs> SendStringCmd => new Lazy<RelayCommand<KeyEventArgs>>(() =>
+            new RelayCommand<KeyEventArgs>(SendString)).Value;
+
+        private void SendString(KeyEventArgs e)
+        {
+            if (e.Key == Key.Enter)
+            {
+                if (string.IsNullOrEmpty(ChatString)) return;
+                Messenger.Default.Send(new ChatInfoModel
+                {
+                    Message = ChatString,
+                    SenderId = _id
+                }, MessageToken.SendChatString);
+                ChatString = string.Empty;
+            }
+        }
+
+        public RelayCommand OpenImageCmd => new Lazy<RelayCommand>(() =>
+            new RelayCommand(OpenImage)).Value;
+
+        private void OpenImage()
+        {
+            var dialog = new OpenFileDialog();
+            if (dialog.ShowDialog() == true)
+            {
+                var fileName = dialog.FileName;
+                if (File.Exists(fileName))
+                {
+                    Messenger.Default.Send(new ChatInfoModel
+                    {
+                        Message = fileName,
+                        SenderId = _id
+                    }, MessageToken.SendChatImage);
+                }
+            }
+        }
+    }
+}