复制代码 代码如下:

private void SaveThumbnail(Bitmap originBitmap, int width, int height, string directory, string filename, string extension)

{

var physicalPath = directory + filename + extension;

using (var newImage = new Bitmap(width, height))

{

using (var graphic = GetGraphic(originBitmap, newImage))

{

graphic.DrawImage(originBitmap, 0, 0, width, height);

using (var encoderParameters = new EncoderParameters(1))

{

encoderParameters.Param[0] = new EncoderParameter(Encoder.Quality, 100L);

newImage.Save(physicalPath,

ImageCodecInfo.GetImageEncoders()

.Where(x => x.FilenameExtension.Contains(extension.ToUpperInvariant()))

.FirstOrDefault(),

encoderParameters);

}

}

}

}

private Graphics GetGraphic(Image originImage, Bitmap newImage)

{

newImage.SetResolution(originImage.HorizontalResolution, originImage.VerticalResolution);

var graphic = Graphics.FromImage(newImage);

graphic.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;

graphic.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;

graphic.PixelOffsetMode = System.Drawing.Drawing2D.PixelOffsetMode.HighQuality;

graphic.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighQuality;

return graphic;

}