/// <summary>
/// 截取图像的矩形区域
/// </summary>
/// <param name="source">源图像对应picturebox1</param>
/// <param name="rect">矩形区域,如上初始化的rect</param>
/// <returns>矩形区域的图像</returns>
public static Image AcquireRectangleImage(Image source, Rectangle rect)
{
if (source == null || rect.IsEmpty) return null;
Bitmap bmSmall = new Bitmap(rect.Width, rect.Height, System.Drawing.Imaging.PixelFormat.Format32bppRgb);
//Bitmap bmSmall = new Bitmap(rect.Width, rect.Height, source.PixelFormat);
using (Graphics grSmall = Graphics.FromImage(bmSmall))
{
grSmall.DrawImage(source, new System.Drawing.Rectangle(0, 0, bmSmall.Width, bmSmall.Height), rect, GraphicsUnit.Pixel);
grSmall.Dispose();
}
return bmSmall;
}