kmpdfkit_demo/Demo/Examples/Compdfkit_Tools/PDFView/PDFViewControl/PDFViewControl.xaml.cs

using ComPDFKit.Tool;
using ComPDFKitViewer;
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Input;

namespace Compdfkit_Tools.PDFControl
{
    public partial class PDFViewControl : UserControl
    {
        public CPDFToolManager PDFToolManager;
        #region Properties
        public CPDFViewerTool PDFViewTool { get; set; }

        public bool CustomSignHandle { get; set; }

        private double[] zoomLevelList = { 1f, 8f, 12f, 25, 33f, 50, 66f, 75, 100, 125, 150, 200, 300, 400, 600, 800, 1000 };
        #endregion
        public PDFViewControl()
        {
            InitializeComponent();
            PDFViewTool = new CPDFViewerTool();
            Content = PDFViewTool;
            PDFViewTool.GetCPDFViewer().MouseWheelZoomHandler += PDFViewControl_MouseWheelZoomHandler;
            PDFToolManager = new CPDFToolManager(PDFViewTool);
            PDFToolManager.SetToolType(CPDFToolManager.ToolType.Viewer);
        }

        private void PDFViewControl_MouseWheelZoomHandler(object sender, ComPDFKitViewer.MouseWheelZoomArgs e)
        {
            if (Keyboard.IsKeyDown(Key.LeftCtrl) || Keyboard.IsKeyDown(Key.RightCtrl))
            {
                e.IsZoom = true;
                PDFViewTool.GetCPDFViewer().SetFitMode(FitModes.FitZoom);
                double zoom= PDFViewTool.GetCPDFViewer().GetZoom();
                PDFViewTool.GetCPDFViewer().SetZoom(CheckZoomLevel(zoom,Convert.ToBoolean(e.WheelBehavior)));
                PDFViewTool.GetCPDFViewer().UpDataRenderFrame();
            }
        }

        #region Private Command Methods
        private double CheckZoomLevel(double zoom, bool IsGrowth)
        {
            double standardZoom = 100;
            if (zoom <= 0.01)
            {
                return 0.01;
            }
            if (zoom >= 10)
            {
                return 10;
            }

            zoom *= 100;
            for (int i = 0; i < zoomLevelList.Length - 1; i++)
            {
                if (zoom > zoomLevelList[i] && zoom <= zoomLevelList[i + 1] && IsGrowth)
                {
                    standardZoom = zoomLevelList[i + 1];
                    break;
                }
                if (zoom >= zoomLevelList[i] && zoom < zoomLevelList[i + 1] && !IsGrowth)
                {
                    standardZoom = zoomLevelList[i];
                    break;
                }
            }
            return standardZoom / 100;
        }
        #endregion

        
    }
}