GDI裁切

Question

有哪位朋友懂得通过MouseDown、MouseMove以及MouseUp这三步实现图像的裁切功能？或者可以在多一步MouseDoubleClick或MouseLeave急求！

Answer 1

/// 裁剪
        /// </summary>
        /// <param name="xPosition">X起始点</param>
        /// <param name="yPosition">Y起始点</param>
        /// <param name="width">宽</param>
        /// <param name="height">高</param>
        public void DrawOutCropArea(int xPosition, int yPosition, int width, int height)
        {
            _bitmapPrevCropArea = (Bitmap)_currentBitmap;
            Bitmap bmap = (Bitmap)_bitmapPrevCropArea.Clone();
            Graphics gr = Graphics.FromImage(bmap);
            Brush cBrush = new Pen(Color.FromArgb(150, Color.White)).Brush;
            Rectangle rect1 = new Rectangle(0, 0, _currentBitmap.Width, yPosition);
            Rectangle rect2 = new Rectangle(0, yPosition, xPosition, height);
            Rectangle rect3 = new Rectangle(0, (yPosition + height), _currentBitmap.Width, _currentBitmap.Height);
            Rectangle rect4 = new Rectangle((xPosition + width), yPosition, (_currentBitmap.Width - xPosition - width), height);
            gr.FillRectangle(cBrush, rect1);
            gr.FillRectangle(cBrush, rect2);
            gr.FillRectangle(cBrush, rect3);
            gr.FillRectangle(cBrush, rect4);
            _currentBitmap = (Bitmap)bmap.Clone();
        }