C#一些常用的图片操作方法：生成文字图片 合并图片等

生成文字图片：

         /// <summary>
         /// 生成文字图片
         /// </summary>
         /// <param name="text"></param>
         /// <param name="isBold"></param>
         /// <param name="fontSize"></param>
         public Image CreateImage(string text, bool isBold, int fontSize)
         {
             int wid = ;
             int high = ;
             Font font;
             if (isBold)
             {
                 font = new Font("Arial", fontSize, FontStyle.Bold);

             }
             else
             {
                 font = new Font("Arial", fontSize, FontStyle.Regular);

             }
             //绘笔颜色
             SolidBrush brush = new SolidBrush(Color.Black);
             StringFormat format = new StringFormat(StringFormatFlags.NoClip);
             Bitmap image = new Bitmap(wid, high);
             Graphics g = Graphics.FromImage(image);
             SizeF sizef = g.MeasureString(text, font, PointF.Empty, format);//得到文本的宽高
             int width = (int)(sizef.Width + );
             int height = (int)(sizef.Height + );
             image.Dispose();
             image = new Bitmap(width, height);
             g = Graphics.FromImage(image);
             g.Clear(Color.White);//透明

             RectangleF rect = new RectangleF(, , width, height);
             //绘制图片
             g.DrawString(text, font, brush, rect);
             //释放对象
             g.Dispose();
             return image;
         }

合并图片：

         /// <summary>
         /// 合并图片
         /// </summary>
         /// <param name="imgBack"></param>
         /// <param name="img"></param>
         /// <returns></returns>
         public static Bitmap CombinImage(Image imgBack, Image img, int xDeviation = , int yDeviation = )
         {

             Bitmap bmp = new Bitmap(imgBack.Width, imgBack.Height + img.Height);

             Graphics g = Graphics.FromImage(bmp);
             g.Clear(Color.White);
             g.DrawImage(imgBack, , , imgBack.Width, imgBack.Height); //g.DrawImage(imgBack, 0, 0, 相框宽, 相框高);     

             //g.FillRectangle(System.Drawing.Brushes.White, imgBack.Width / 2 - img.Width / 2 - 1, imgBack.Width / 2 - img.Width / 2 - 1,1,1);//相片四周刷一层黑色边框    

             //g.DrawImage(img, 照片与相框的左边距, 照片与相框的上边距, 照片宽, 照片高);    

             g.DrawImage(img, imgBack.Width /  - img.Width /  + xDeviation, imgBack.Height + yDeviation, img.Width, img.Height);
             GC.Collect();
             return bmp;
         }    

         /// <summary>
         /// Resize图片
         /// </summary>
         /// <param name="bmp">原始Bitmap</param>
         /// <param name="newW">新的宽度</param>
         /// <param name="newH">新的高度</param>
         /// <param name="mode">保留着，暂时未用</param>
         /// <returns>处理以后的图片</returns>
         public static Image ResizeImage(Image bmp, int newW, int newH, int mode)
         {
             try
             {
                 Image b = new Bitmap(newW, newH);
                 Graphics g = Graphics.FromImage(b);

                 // 插值算法的质量
                 g.InterpolationMode = InterpolationMode.HighQualityBicubic;
                 g.DrawImage(bmp, new Rectangle(, , newW, newH), new Rectangle(, , bmp.Width, bmp.Height),
                             GraphicsUnit.Pixel);
                 g.Dispose();
                 return b;
             }
             catch
             {
                 return null;
             }
         }    

MemoryStream保存到图片

         Bitmap bmp = CombinImage(ms, img1);
         MemoryStream ms = new MemoryStream();
         bmp.Save(ms, ImageFormat.Png);