protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            {


                string path = Server.MapPath(@"/Content/images/bg/index_01.jpg");
                AddToImg(path, "圖片測試pictureBox在圖片上繪制文本_百度知道pictureBox在圖片上繪制文本_百度知道", Guid.NewGuid().ToString("N"));
            }
        }

using System.IO;
using System.Text;
using System.Drawing;
using System.Drawing.Drawing2D;

繪制圖片和文字

        /// <summary>
        /// 指定圖片添加指定文字
        /// </summary>
        /// <param name="fileName">指定文件路徑</param>
        /// <param name="text">添加的文字</param>
        /// <param name="picname">
 
生成文件名</param>

        private void AddToImg(string file, string text, string picname)
        {
            //判斷指定圖片是否存在
            //if (!File.Exists(MapPath(fileName)))
            //{
            //    throw new FileNotFoundException("The file don‘t exist!");
            //}

            if
 
 (text == string.Empty)
            {
                return;
            }


            System.Drawing.Image image = System.Drawing.Image.FromFile(file);
            Bitmap bitmap = new Bitmap(image, image.Width, image.Height);
            Graphics g = Graphics.FromImage(bitmap);

            float fontSize = 40.0f;             //字體大小
            float textWidth = text.Length * fontSize;  //文本的長度
            //下面定義一個矩形區域，以後在這個矩形裏畫上白底黑字
            float rectX = 120;
            float rectY = 200;
            float rectWidth = 200;  // text.Length * (fontSize + 40);
            float rectHeight = fontSize + 40;
            //聲明矩形域
            RectangleF textArea = new RectangleF(rectX, rectY, 270, 270);


           
            Font font = new Font("華文隸書", fontSize, FontStyle.Bold);   //定義字體
            Font font2 = new Font("楷體", fontSize, FontStyle.Bold);   //定義字體
            //font.Bold = true;

            Brush whiteBrush = new SolidBrush(Color.DodgerBlue);   //白筆刷，畫文字用
            //Brush blackBrush = new SolidBrush(Color.Black);   //黑筆刷，畫背景用

            //g.FillRectangle(blackBrush, rectX, rectY, rectWidth, rectHeight);

            g.DrawString(text, font, whiteBrush, textArea, StringFormat.GenericDefault);

            g.DrawString(text, font, whiteBrush, new RectangleF(rectX, image.Height/2, 270, 270));

            g.DrawString("168元", font2, new SolidBrush(Color.Firebrick), new RectangleF(rectX, image.Height - 150, rectWidth, rectHeight));

            ////-------------------  繪制高質量 -------------------------------------------
            //設置 System.Drawing.Graphics對象的SmoothingMode屬性為HighQuality 
            g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
            //下面這個也設成高質量 
            g.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighQuality;
            //下面這個設成High 
            g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High;

            //畫專屬推廣二維碼
            System.Drawing.Image qrCodeImage = System.Drawing.Image.FromFile(Server.MapPath(@"/Content/images/money-cards.png"));
            g.DrawImage(qrCodeImage, new Rectangle(image.Width - qrCodeImage.Width - 200,
            image.Height - qrCodeImage.Height - 200,
            qrCodeImage.Width,
            qrCodeImage.Height),
            0, 0, qrCodeImage.Width, qrCodeImage.Height, GraphicsUnit.Pixel);
            //畫微信昵稱
            g.DrawString("小馬快跑", font, new SolidBrush(Color.Red), new Rectangle(image.Width - qrCodeImage.Width - 200,
            image.Height - qrCodeImage.Height - 300,
            qrCodeImage.Width + 100,
            50));

            MemoryStream ms = new MemoryStream();

            //輸出方法一：將文件生成並保存到C盤
            string path = "D:\\test\\" + picname + ".png";
            bitmap.Save(path, System.Drawing.Imaging.ImageFormat.Jpeg);


            //輸出方法二，顯示在網頁中，保存為Jpg類型
            //bitmap.Save(ms, ImageFormat.Jpeg);
            //Response.Clear();
            //Response.ContentType = "image/jpeg";
            //Response.BinaryWrite(ms.ToArray());

            g.Dispose();
            bitmap.Dispose();
            image.Dispose();
        }

C# 生成海報，文本區域指定和換行，圖片合成