C# .net Core 图片缩放和压缩
/// <summary>
/// 按宽度缩放
/// </summary>
/// <param name="bmp"></param>
/// <param name="width"></param>
/// <returns></returns>
private static Image Resizer(this Image bmp, int width)
{
if (bmp.Width < width || width == 0) return bmp;
Bitmap ob = new Bitmap(width, bmp.Height * width / bmp.Width);
using (var g = Graphics.FromImage(ob))
{
g.Clear(Color.WhiteSmoke);
g.DrawImage(bmp, new Rectangle(0, 0, ob.Width, ob.Height), 0, 0, bmp.Width, bmp.Height, GraphicsUnit.Pixel);
}
return ob;
}
/// <summary>
/// path:路径；quality：质量；
/// </summary>
/// <param name="bmp"></param>
/// <param name="path">路径</param>
/// <param name="quality">质量</param>
public static void Save(this Image bmp, string path, int quality)
{
EncoderParameters eps = new EncoderParameters();
eps.Param[0] = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, quality);
bmp.Save(path, ImageCodecInfo.GetImageEncoders().FirstOrDefault(x => x.FormatID == ImageFormat.Jpeg.Guid), eps);
}
