PDFOffice_Windows_exe/PDF Office/ViewModels/PropertyPanel/ViewModular/ReadModeContentViewModel.cs

using ComPDFKitViewer.PdfViewer;
using Dropbox.Api.Sharing;
using PDF_Office.Helper;
using PDF_Office.Model;
using Prism.Commands;
using Prism.Mvvm;
using Prism.Regions;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading.Tasks;
using System.Windows.Controls;
using System.Windows.Forms;
using System.Windows.Input;
using static System.Windows.Forms.VisualStyles.VisualStyleElement.TrayNotify;
using System.Windows.Media;
using KeyEventArgs = System.Windows.Input.KeyEventArgs;
using TextBox = System.Windows.Controls.TextBox;
using static System.Windows.Forms.VisualStyles.VisualStyleElement;

namespace PDF_Office.ViewModels.PropertyPanel.ViewModular
{
    public class ReadModeContentViewModel : BindableBase, INavigationAware
    {
        private ViewContentViewModel viewContentViewModel;
        private CPDFViewer PDFViewer;

        private int currentPage;

        public int CurrentPage
        {
            get { return currentPage; }
            set
            {
                SetProperty(ref currentPage, value);
            }
        }

        private int pageCount;

        public int PageCount
        {
            get { return pageCount; }
            set
            {
                SetProperty(ref pageCount, value);
            }
        }

        public DelegateCommand<object> KeyDownCommand { get; set; }
        public DelegateCommand<object> PreviewKeyDownCommand { get; set; }
        public DelegateCommand<object> ZoomOutCommand { get; set; }
        public DelegateCommand<object> ZoomInCommand { get; set; }
        public DelegateCommand<object> PrePageCommand { get; set; }
        public DelegateCommand<object> NextPageCommand { get; set; }

        public ReadModeContentViewModel()
        {
            KeyDownCommand = new DelegateCommand<object>(KeyDownEvent);
            PreviewKeyDownCommand = new DelegateCommand<object>(PreviewKeyDownEvent);
            ZoomOutCommand = new DelegateCommand<object>(PageZoomOutEvent);
            ZoomInCommand = new DelegateCommand<object>(PageZoomInEvent);

            PrePageCommand = new DelegateCommand<object>(PrePageEvent);
            NextPageCommand = new DelegateCommand<object>(NextPageEvent);
        }

        private void NextPageEvent(object obj)
        {
            if (PDFViewer.ModeView == ComPDFKitViewer.ViewMode.Double || PDFViewer.ModeView == ComPDFKitViewer.ViewMode.DoubleContinuous || PDFViewer.ModeView == ComPDFKitViewer.ViewMode.Book || PDFViewer.ModeView == ComPDFKitViewer.ViewMode.BookContinuous)

            {
                PDFViewer.GoToPage(PDFViewer.CurrentIndex + 2);
            }
            else
                PDFViewer.GoToPage(PDFViewer.CurrentIndex + 1);
        }

        private void PrePageEvent(object obj)
        {
            if (PDFViewer.ModeView == ComPDFKitViewer.ViewMode.Double || PDFViewer.ModeView == ComPDFKitViewer.ViewMode.DoubleContinuous || PDFViewer.ModeView == ComPDFKitViewer.ViewMode.Book || PDFViewer.ModeView == ComPDFKitViewer.ViewMode.BookContinuous)
            {
                PDFViewer.GoToPage(PDFViewer.CurrentIndex - 1);
            }
            else
            {
                PDFViewer.GoToPage(PDFViewer.CurrentIndex - 1);
            }
        }

        private void PageZoomInEvent(object obj)
        {
            double zoom = PDFViewer.ZoomFactor * 100;
            zoom = zoom + 25;
            if (zoom != 0 && zoom <= 1000 && PDFViewer != null)
            {
                PDFViewer.Zoom(zoom / 100);
            }
        }

        private void PageZoomOutEvent(object obj)
        {
            double zoom = PDFViewer.ZoomFactor * 100;
            zoom = zoom - 25;
            if (zoom != 0 && PDFViewer != null)
            {
                PDFViewer.Zoom(zoom / 100);
            }
        }

        private void PreviewKeyDownEvent(object obj)
        {
            var args = obj as KeyEventArgs;
            if (args != null)
            {
                //显示文本框输入内容
                List<Key> NumberKeys = new List<Key>() { Key.D0,Key.D1,Key.D2,Key.D3,Key.D4,Key.D5,Key.D6,Key.D7,Key.D8,Key.D9,Key.NumPad0,Key.NumPad1,Key.NumPad2,Key.NumPad3,Key.NumPad4,Key.NumPad5,Key.NumPad6,Key.NumPad7,Key.NumPad8,Key.NumPad9,Key.Delete,Key.Back,Key.Enter,Key.Right,Key.Left};
                if (!NumberKeys.Contains(args.Key))
                {
                    args.Handled = true;
                }
            }
        }

        private void KeyDownEvent(object obj)
        {
            if (obj is CompositeCommandParameter objs)
            {
                if (objs.EventArgs is System.Windows.Input.KeyEventArgs keyEventArgs)
                {
                    TextBlock textBlock = objs.Parameter as TextBlock;
                    if (keyEventArgs.Key == Key.Enter)
                    {
                        if (keyEventArgs.OriginalSource is System.Windows.Controls.TextBox txtCurrentPageNum)
                        {
                            int pagenum = 0;
                            string text = txtCurrentPageNum.Text.ToString();
                            char[] chs = { ' ', '/', '\\' };//字符截取  拒止非法输入
                            int i = text.LastIndexOfAny(chs);
                            if (i > 0)
                            {
                                text = text.Substring(0, i - 1);
                            }
                            if (!int.TryParse(text, out pagenum))
                            {
                                CurrentPage = PDFViewer.Document.PageCount;
                                txtCurrentPageNum.Text = PDFViewer.Document.PageCount.ToString();
                                return;
                            }
                            if (pagenum < 1)
                            {
                                pagenum = 1;
                            }
                            else if (pagenum > PDFViewer.Document.PageCount)
                            {
                                pagenum = PDFViewer.Document.PageCount;
                            }

                            PDFViewer.GoToPage(pagenum - 1);
                            CurrentPage = pagenum;
                            txtCurrentPageNum.Text = pagenum.ToString();
                            textBlock.Visibility = System.Windows.Visibility.Visible;
                            txtCurrentPageNum.Background = new SolidColorBrush(Colors.Transparent);
                            txtCurrentPageNum.MoveFocus(new TraversalRequest(FocusNavigationDirection.Next));
                        }
                    }
                }
            }
        }

        public bool IsNavigationTarget(NavigationContext navigationContext)
        {
            return true;
        }

        public void OnNavigatedFrom(NavigationContext navigationContext)
        {
        }

        public void OnNavigatedTo(NavigationContext navigationContext)
        {
            var viewContentViewModel = navigationContext.Parameters[ParameterNames.ViewContentViewModel] as ViewContentViewModel;
            if (viewContentViewModel != null)
            {
                this.viewContentViewModel = viewContentViewModel;
            }
            var pdfview = navigationContext.Parameters[ParameterNames.PDFViewer] as CPDFViewer;
            if (pdfview != null)
            {
                //获取页面设置等信息
                this.PDFViewer = pdfview;
                PageCount = PDFViewer.Document.PageCount;
                CurrentPage = PDFViewer.CurrentIndex + 1;
                this.PDFViewer.InfoChanged += PDFViewer_InfoChanged;
            }
        }

        private void PDFViewer_InfoChanged(object sender, KeyValuePair<string, object> e)
        {
            if (e.Key == "SplieMode" || e.Key == "ViewMode")
            {
                return;
            }
            PageCount = PDFViewer.Document.PageCount;
            CurrentPage = PDFViewer.CurrentIndex + 1;
        }
    }
}