日期:2014-05-17  浏览次数:22084 次

drawImage失真
直接在打印中drawstring,字体不失真,若先外部整理成image,然后再通过drawimage字体就非常模糊,为什么?
C# code

private void button1_Click(object sender, EventArgs e)
        {
            PrintDocument printDocument = new PrintDocument();
            printDocument.DocumentName = "测试文档";//设置完后可在打印对话框及队列中显示(默认显示document)

            //打印输出(过程)            
            printDocument.PrintPage += new PrintPageEventHandler(printDocument_PrintPage);

            PrintPreviewDialog ppd = new PrintPreviewDialog();
            ppd.Document = printDocument;
            try
            {//显示打印预览窗口
                ppd.WindowState = FormWindowState.Maximized;
                ppd.ShowDialog();

            }
            catch (Exception excep)
            {
                //显示打印出错消息
                MessageBox.Show(excep.Message, "打印出错", MessageBoxButtons.OK, MessageBoxIcon.Error);
            }
        }

        Bitmap imageDraw()
        {
            Bitmap bitmap = new Bitmap(50, 50);
            SolidBrush drawBrush = new SolidBrush(Color.Black);
            StringFormat drawFormat = new StringFormat();
            using (Graphics g = Graphics.FromImage(bitmap))
            {
                g.DrawString("小字体测试", new Font("宋体", 6), drawBrush, 2, 2, drawFormat);
            }
            return bitmap;
        }

        void printDocument_PrintPage(object sender, PrintPageEventArgs e)
        {
            Graphics g = e.Graphics;
            // 指定高质量的双三次插值法。执行预筛选以确保高质量的收缩。此模式可产生质量最高的转换图像。  
            g.InterpolationMode = InterpolationMode.HighQualityBicubic;
            // 指定高质量、低速度呈现。  
            g.SmoothingMode = SmoothingMode.HighQuality;
            Bitmap image = imageDraw();
            g.DrawImage(image, new Rectangle(100, 100, image.Width, image.Height), new Rectangle(0, 0, image.Width, image.Height), GraphicsUnit.Pixel);

            SolidBrush drawBrush = new SolidBrush(Color.Black);
            StringFormat drawFormat = new StringFormat();
            g.DrawString("直接刷字测试", new Font("宋体", 6), drawBrush, 200, 200, drawFormat);
            e.HasMorePages = false;
        }




------解决方案--------------------
前者以文字方式打印,后者以图像方式打印,文字可保真,图像会因适应打印分辨率而失真。