添加项目文件。

ViewModels/ChatMdViewModel.cs

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+using Markdig.Wpf;
+using OllamaSharp;
+using System.ComponentModel;
+using System.Diagnostics;
+using System.IO;
+using System.Runtime.CompilerServices;
+using System.Windows.Controls;
+using System.Windows.Input;
+using YwxApp.AiChat.Commands;
+
+namespace YwxApp.AiChat.ViewModels
+{
+    /// <summary>
+    /// 0、Current class:
+    /// </summary>
+    public class ChatMdViewModel : INotifyPropertyChanged
+    {
+        #region Field | Property | Collection | Command
+
+        #region Field
+        private string? _inputText;                  //User input text.
+        private Chat? chat;                          //Build interactive chat.
+        private ShareOllamaObject _ollama;           //share Ollama object.
+        private CancellationTokenSource _cancellationTokenSource;   //Termination chat Token
+
+        private bool _useExtensions = true;         //whether enable Markdown extensions function.
+        private string _markdownContent;            //Markdown context.
+
+        private MarkdownViewer markdownViewer;      //Markdwon viewer.
+        private bool _isAutoScrolling = false;      //whather enable scroll 
+
+        private double _textWidth;                     // MarkdownViewer width
+        #endregion
+
+        #region Property : Support property changed notify. 
+        //InputText：
+        public string? InputText
+        {
+            get => _inputText;
+            set
+            {
+                _inputText = value;
+                OnPropertyChanged();
+            }
+        }
+        public string MarkdownContent
+        {
+            get => _markdownContent;
+            set
+            {
+                _markdownContent = value;
+                // Notify property changed if needed
+                OnPropertyChanged();
+            }
+        }
+
+
+        public double TextWidth
+        {
+            get => _textWidth;
+            set
+            {
+                _textWidth = value;
+                OnPropertyChanged();
+            }
+        }
+        #endregion
+
+        #region Collection:
+        #endregion
+
+        #region Command: Builde Command： generate response command
+        public ICommand? SubmitQuestionCommand { get; }
+        //stop current chat
+        public ICommand? StopCurrentChatCommand { get; }
+        //new chat
+        public ICommand? NewSessionCommand { get; }
+        //scroll to MarkdownViewer  end  command
+        public ICommand ScrollToEndCommand { get; }
+
+        #endregion
+
+        #endregion
+
+        #region Constructor : Initialize
+        public ChatMdViewModel()
+        {
+            // initialize object
+            markdownViewer = new MarkdownViewer();
+            _cancellationTokenSource = new CancellationTokenSource();
+
+            //generate command
+            SubmitQuestionCommand = new ParameterlessCommand(async () => OnSubmitQuestion());
+            StopCurrentChatCommand = new ParameterlessCommand(OnStopCurrentChat);
+            NewSessionCommand = new ParameterlessCommand(OnNewSessionCommand);
+
+            //markdown reletive command
+            ScrollToEndCommand = new ScrollViewerCommand(OnScrollToEnd);
+
+            OnLoadRecord();
+        }
+        #endregion
+
+        #region other method
+
+        #region other
+        //setting Ollama
+        public void SetOllama(ShareOllamaObject ollama)
+        {
+            _ollama = ollama;
+        }
+        //check chat state
+        private bool CheckChatState()
+        {
+            if (_ollama.Ollama == null || _ollama.OllamaEnabled == false)
+            {
+                MarkdownContent += "server not open...";
+                return false;
+            }
+            if (_ollama.Ollama.SelectedModel == null)
+            {
+                MarkdownContent += "model not select...";
+                return false;
+            }
+            if (string.IsNullOrWhiteSpace(InputText))
+            {
+                MarkdownContent += "text is null ...";
+                return false;
+            }
+            return true;
+        }
+
+        //trigger sroll to end
+        private void OnScrollToEnd(object parameter)
+        {
+            var scrollViewer = parameter as ScrollViewer;
+            if (scrollViewer != null && _isAutoScrolling)
+            {
+                scrollViewer.ScrollToEnd();
+                TextWidth = scrollViewer.Width;
+            }
+        }
+        #endregion
+
+        #region Mardown command binding method 
+        //loaded history record
+        public void OnLoadRecord()
+        {
+            OutText(File.ReadAllText($"{Environment.CurrentDirectory}//Data//" +
+                $"{DateTime.Today.ToString("yyyyMMdd")}//{DateTime.Today.ToString("yyyyMMdd")}_0.txt"));
+        }
+
+        #endregion
+
+        #endregion
+
+        #region command method
+        /// <summary>
+        /// Submit question:  Submit problem to the AI and get the output result
+        /// </summary>
+        private async void OnSubmitQuestion()
+        {
+            try
+            {
+                // Checks whether the string is empty, empty, or contains only whitespace characters
+                if (CheckChatState())
+                {
+                    _isAutoScrolling = true;            //enable auto scroll
+                    //ToggleExtensions();
+                    string input = InputText;
+                    InputText = string.Empty;
+                    string output = string.Empty;
+                    OutText($"{Environment.NewLine}");
+                    OutText($"## 【User】{Environment.NewLine}");
+                    OutText($">{input}{Environment.NewLine}");
+                    OutText($"## 【AI】{Environment.NewLine}");
+                    //
+                    output += ($"{Environment.NewLine}");
+                    output += ($"## 【User】{Environment.NewLine}");
+                    output += ($">{input}{Environment.NewLine}");
+                    output += ($"## 【AI】{Environment.NewLine}");
+
+                    if (input.Equals("/clearContext"))
+                    {
+                        chat = new Chat(_ollama.Ollama);
+                        _ollama.RecordIndex++;
+                        return;
+                    }
+                    #region Start answer :Mode two => chat mode 
+                    if (chat == null)
+                    {
+                        chat = new Chat(_ollama.Ollama);
+                        _ollama.RecordIndex++;
+                    }
+                    _cancellationTokenSource = new CancellationTokenSource();
+                    await foreach (var answerToken in chat.SendAsync(input, _cancellationTokenSource.Token))
+                    {
+
+                        OutText(answerToken);
+                        output += (answerToken);
+                        await Task.Delay(20);
+                        Debug.Print(answerToken);
+                    }
+                    OutText($"{Environment.NewLine}");
+                    _ollama.WriteDataToFileAsync(output);
+                    #endregion
+                }
+            }
+            catch (Exception ex)
+            {
+                OutText($"Error: {ex.Message}{Environment.NewLine}");
+            }
+            _isAutoScrolling = false;
+        }
+
+        /// <summary>
+        /// New build chat.
+        /// </summary>
+        private void OnNewSessionCommand()
+        {
+            OnStopCurrentChat();
+            if (chat != null)
+            {
+                chat.SendAsync("/clearContext");
+                if (_ollama != null)
+                    chat = new Chat(_ollama.Ollama);
+            }
+            OutText($"{string.Empty}{Environment.NewLine}");
+        }
+        /// <summary>
+        /// stop chat.
+        /// </summary>
+        private void OnStopCurrentChat()
+        {
+            _cancellationTokenSource?.Cancel();
+            Task.Delay(100);
+            OutText($"{string.Empty}{Environment.NewLine}");
+            MarkdownContent = string.Empty;
+        }
+        /// <summary>
+        /// output Text to Markdown.
+        /// </summary>
+        /// <param name="text"></param>
+        public void OutText(string text)
+        {
+            MarkdownContent += text;
+        }
+        #endregion
+
+        #region Method that trigger a property changed event.
+        /// <summary>
+        /// OnPropertyChanged：Trigger a property changed event.
+        /// </summary>
+        public event PropertyChangedEventHandler? PropertyChanged;
+        protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
+        {
+            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
+        }
+        #endregion
+    }
+}