把文本轉成圖片的C#代碼

通過系統Graphics繪圖把文字繪制到位圖上，然後顯示或保存起來，這裡用定義該函數

        /// <summary>
        /// 把文字轉換才Bitmap
        /// </summary>
        /// <param name="text"></param>
        /// <param name="font"></param>
        /// <param name="rect">用於輸出的矩形，文字在這個矩形內顯示，為空時自動計算</param>
        /// <param name="fontcolor">字體顏色</param>
        /// <param name="backColor">背景顏色</param>
        /// <returns></returns>
        private Bitmap TextToBitmap(string text, Font font, Rectangle rect, Color fontcolor, Color backColor)
        {
            Graphics g;
            Bitmap bmp;
            StringFormat format = new StringFormat(StringFormatFlags.NoClip);
            if (rect == Rectangle.Empty)
            {
                bmp = new Bitmap(1, 1);
                g = Graphics.FromImage(bmp);
                //計算繪制文字所需的區域大小（根據寬度計算長度），重新創建矩形區域繪圖
                SizeF sizef = g.MeasureString(text, font, PointF.Empty, format);

                int width = (int)(sizef.Width + 1);
                int height = (int)(sizef.Height + 1);
                rect = new Rectangle(0, 0, width, height);
                bmp.Dispose();

                bmp = new Bitmap(width, height);
            }
            else
            {
                bmp = new Bitmap(rect.Width, rect.Height);
            }

            g = Graphics.FromImage(bmp);

            //使用ClearType字體功能
            g.TextRenderingHint = System.Drawing.Text.TextRenderingHint.ClearTypeGridFit;
            g.FillRectangle(new SolidBrush(backColor), rect);
            g.DrawString(text, font, Brushes.Black, rect, format);
            return bmp;
        }

把textbox1文本的內容輸出為jpg圖片

            //獲取文本
            string text = this.textbox1.Text;

            //得到Bitmap(傳入Rectangle.Empty自動計算寬高)
            Bitmap bmp = TextToBitmap(text, this.textbox1.Font, Rectangle.Empty, this.textbox1.ForeColor, this.textbox1.BackColor);
            
            //用PictureBox顯示
            this.pbTextView.Image = bmp;

            //保存到桌面save.jpg
            string directory = System.Environment.GetFolderPath(System.Environment.SpecialFolder.DesktopDirectory);
            bmp.Save(directory + "\\save.jpg", ImageFormat.Jpeg);