A Tool to Clip Images

using Microsoft.Win32;
using System;
using System.IO;
using System.Text.RegularExpressions;
using System.Windows;
using System.Windows.Media.Imaging;

namespace Clip
{
    class Clip
    {
        [STAThread]
        static void Main(string[] args)
        {
            var openFileDialog = new OpenFileDialog()
            {
                Filter = "所有图片文件|*.bmp;*.dib;*.jpg;*.jpeg;*.jpe;*.jfif;*.png|位图文件|*.bmp;*.dib|JPEG|*.jpg;*.jpeg;*.jpe;*.jfif|PNG|*.png"
            };
            while (openFileDialog.ShowDialog() != true) ;
            var bitmapImage = new BitmapImage(new Uri(openFileDialog.FileName));
            Console.WriteLine("Left Margin: ");
            Console.WriteLine("Top Margin: ");
            Console.WriteLine("Right Margin: ");
            Console.WriteLine("Bottom Margin: ");
            Console.CursorTop = ;
            Console.CursorLeft = ;
            int leftMargin = int.Parse(Console.ReadLine());
            Console.CursorLeft = ;
            int topMargin = int.Parse(Console.ReadLine());
            Console.CursorLeft = ;
            int rightMargin = int.Parse(Console.ReadLine());
            Console.CursorLeft = ;
            int bottomMargin = int.Parse(Console.ReadLine());
            int width = bitmapImage.PixelWidth - leftMargin - rightMargin;
            int height = bitmapImage.PixelHeight - topMargin - bottomMargin;
            var writeableBitmap = new WriteableBitmap(width, height, bitmapImage.DpiX, bitmapImage.DpiY, bitmapImage.Format, bitmapImage.Palette);
            IntPtr backBuffer = writeableBitmap.BackBuffer;
            bitmapImage.CopyPixels(new Int32Rect(leftMargin, topMargin, width, height), backBuffer, height * writeableBitmap.BackBufferStride, writeableBitmap.BackBufferStride);
            var saveFileDialog = new SaveFileDialog()
            {
                Filter = "所有图片文件|*.bmp;*.dib;*.jpg;*.jpeg;*.jpe;*.jfif;*.png|位图文件|*.bmp;*.dib|JPEG|*.jpg;*.jpeg;*.jpe;*.jfif|PNG|*.png"
            };
            while (saveFileDialog.ShowDialog() != true) ;
            BitmapEncoder bitmapEncoder = null;
            if (Regex.IsMatch(saveFileDialog.SafeFileName, @"^.+\.(?:bmp|dib)$"))
            {
                bitmapEncoder = new BmpBitmapEncoder();
            }
            else if (Regex.IsMatch(saveFileDialog.SafeFileName, @"^.+\.(?:jpg|jpeg|jpe|jfif)$"))
            {
                bitmapEncoder = new JpegBitmapEncoder();
            }
            else if (Regex.IsMatch(saveFileDialog.SafeFileName, @"^.+\.(?:png)$"))
            {
                bitmapEncoder = new PngBitmapEncoder();
            }
            bitmapEncoder.Frames.Add(BitmapFrame.Create(writeableBitmap));
            var fileStream = new FileStream(saveFileDialog.FileName, FileMode.Create);
            bitmapEncoder.Save(fileStream);
        }
    }
}