c# 实现图片中45度角间隔显示文字水印 可用与电商项目中显示入住商城商户的资料信息外部展示 用于添加水印效果

/// <summary>
        /// 添加水印
        /// </summary>
        /// <param name="imgPath">原图片地址</param>
        /// <param name="sImgPath">水印图片地址</param>
        /// <returns>resMsg[0] 成功,失败 </returns>
        public static string[] AddWaterMark(string imgPath, string sImgPath)
        {
            string[] resMsg = new[] { "成功", sImgPath };
            using (Image image = Image.FromFile(imgPath))
            {
                try
                {
                    Bitmap bitmap = new Bitmap(image);
                    Color markcolor = Color.Red;
                    int degree = 45;
                   //图片的宽度与高度
                    int width = bitmap.Width, height = bitmap.Height;
                    
                    //水印文字
                    string text = "****入驻专用 其他无效";

                     Graphics g = Graphics.FromImage(bitmap);
                   
                    int rowsNumber, columnsNumber;
                  //图片宽度与高度 用于横向与竖向水印文字
                    if (width > height) {
                     rowsNumber = height /20;
                     columnsNumber = width / 200;
                    }else { 
                    rowsNumber = height /200;
                     columnsNumber = width / 20;
                    }
                    if (rowsNumber < 1)
                    {
                        rowsNumber = 1;
                    }
                    if (columnsNumber < 1)
                    {
                        columnsNumber = 1;
                    }

                   
                    g.DrawImage(bitmap, 0, 0);

                    g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High;

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

                    g.DrawImage(image, new Rectangle(0, 0, width, height), 0, 0, width, height, GraphicsUnit.Pixel);

                    Font crFont = new Font("微软雅黑", 12, FontStyle.Bold);
                    SizeF crSize = new SizeF();
                    crSize = g.MeasureString(text, crFont);

                   

                    SolidBrush semiTransBrush = new SolidBrush(Color.FromArgb(120, 137, 131, 131));

                    //将原点移动 到图片中点
                    g.TranslateTransform(0 , height );
                    //以原点为中心 转 -45度
                    g.RotateTransform(-45);

                    for (int j = 0; j < rowsNumber; j++)
                    {
                        for (int i = 0; i < columnsNumber; i++)
                        {
                           
                            g.DrawString(text, crFont, semiTransBrush, new PointF(i * 100 + j * 200, -i * 100 + j * 200));
                        }
                    }

                  
                    //保存文件
                      bitmap.Save(sImgPath, System.Drawing.Imaging.ImageFormat.Jpeg);

                }
                catch (Exception e)
                {

                    resMsg[0] = "失败";
                    resMsg[1] = e.Message;
                }
            }

            return resMsg;
        }