C#中Bitmap類實現對映像操作的一些方法(Asp.net(C#)-放大縮小圖片尺寸)

匯入以下兩個包：
    System.Drawing;
      System.Drawing.Imaging;
建產對象：
     Bitmap bm = new Bitmap("c:/1.bmp");
縮放：
     Bitmap bm1 = new Bitmap(bm,width,height);
格式轉換：
     bm.save("c:/1.jpg",ImageFromat.Jpeg);
     bm1.Save("c:/1.gif", ImageFormat.Gif);
剪下一個地區：
     //剪下大小
    int cutwidth;
      int cutheight;
     Graphics g;
     //以大小為剪下大小，像素格式為32位RGB建立一個位元影像對像
     Bitmap bm1 = new Bitmap(width,height,PixelFormat.Format32bppRgb) ;
    //定義一個地區
     Rectangle rg = new Rectangle(0,0,cutwidth,cutheight);
     //要繪製到的位元影像
     g = Graphics.FromImage(bm1);
     //將bm內rg所指定的地區繪製到bm1
     g.DrawImage(bm,rg)

 

Asp.net(C#)-放大縮小圖片尺寸

 /// <summary>
    /// 放大縮小圖片尺寸
    /// </summary>
    /// <param name="picPath"></param>
    /// <param name="reSizePicPath"></param>
    /// <param name="iSize"></param>
    /// <param name="format"></param>
    public void PicSized(string picPath, string reSizePicPath, int iSize, ImageFormat format)
    {
        Bitmap originBmp = new Bitmap(picPath);
        int w = originBmp.Width * iSize;
        int h = originBmp.Height * iSize;
        Bitmap resizedBmp = new Bitmap(w, h);
        Graphics g = Graphics.FromImage(resizedBmp);
        //設定高品質插值法  
        g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High;
        //設定高品質,低速度呈現平滑程度  
        g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
        g.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighQuality;
        //消除鋸齒
        g.SmoothingMode = SmoothingMode.AntiAlias;
        g.DrawImage(originBmp, new Rectangle(0, 0, w, h), new Rectangle(0, 0, originBmp.Width, originBmp.Height), GraphicsUnit.Pixel);
        resizedBmp.Save(reSizePicPath, format);
        g.Dispose();
        resizedBmp.Dispose();
        originBmp.Dispose();
    }