Png图片合并

 private void UnitEdgeTile(ArrayList filename, string edgeTileFile)
    {
        int l = filename.Count;
        System.Drawing.Bitmap[] bmp = new Bitmap[l];
        System.Drawing.Bitmap bmp1 = new System.Drawing.Bitmap(256, 256, PixelFormat.Format32bppArgb);
        System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(bmp1);
        for (int i = 0; i < l; i++)
        {
            bmp[i] = new System.Drawing.Bitmap((string)filename[i]);
            g.DrawImage(bmp[i], new System.Drawing.Point(0, 0));
        }
        bmp1.Save(edgeTileFile);
    }