應用程式的私用字型

<%@ WebHandler Language="C#" Class="Word" %>

using System;

using System.Web;

using System.Drawing;

using System.Drawing.Imaging;

using System.Linq;

using System.Drawing.Text;

using System.Web.Hosting;

using System.Drawing.Drawing2D;

public class Word : IHttpHandler

{

    //為避免在Web Server上要加裝字型檔的部署需求，自行載入字型

    static PrivateFontCollection myOwnFonts = 

        new PrivateFontCollection();

    //在靜態建構式中載入

    static Word()

    {

        //截入預先準備好的字型檔案

        myOwnFonts.AddFontFile(

            HostingEnvironment.MapPath("~/App_Data/TRACE.TTF"));

    }

    //傳入字型大小，取得Font物件    

    private static Font GetTraceFont(float fontSz)

    {

        return new Font(myOwnFonts.Families[0], fontSz);

    }

    //建立一個虛的Graphic物件，以便MeasureString預測字型尺寸

    static Bitmap bmpPreview = new Bitmap(10, 10);

    static Graphics gPreview = Graphics.FromImage(bmpPreview);

    private static Size MeasureSize(string text, float fontSz)

    {

        lock (gPreview) //For Thread-Safe

        {

            return gPreview.MeasureString(text, 

                GetTraceFont(fontSz)).ToSize();

        }

    }

    public void ProcessRequest(HttpContext context)

    {

        float fs; //Font Size 字型大小

        if (!float.TryParse(context.Request["fs"], out fs)) fs = 96;

        string txt = context.Request["t"] ?? "Darkthread";

        int pd; //Padding 上下留白

        if (!int.TryParse(context.Request["pd"], out pd)) pd = 15;

        //預測文字尺寸

        Size estSize = MeasureSize(txt, fs);

        //由文字尺寸決定寬、高

        int w = estSize.Width + pd * 2;

        int.TryParse(context.Request["w"] ?? w.ToString(), out w);

        int h = estSize.Height + pd * 2;

        Color bc = ColorTranslator.FromHtml("0x" + //背景色

            (context.Request["bc"] ?? "005f00"));

        Color fc = ColorTranslator.FromHtml("0x" + //前景色

            (context.Request["fc"] ?? "ffffff"));

        Color lc = ColorTranslator.FromHtml("0x" + //輔助線顏色

            (context.Request["lc"] ?? "ffff00"));

        //建立畫布

        Bitmap bmp = new Bitmap(w, h);

        Graphics g = Graphics.FromImage(bmp);

        //塗上背景色

        Brush p = new SolidBrush(bc);

        g.FillRectangle(p, 0, 0, bmp.Width, bmp.Height);

        //設定文字反鋸齒

        g.TextRenderingHint = TextRenderingHint.AntiAlias;

        //劃輔助線

        Pen pen = new Pen(new SolidBrush(lc));

        foreach (int y in 

            new int[] { pd, pd + estSize.Height * 2 /3, pd + estSize.Height })

            g.DrawLine(pen, 0, y, bmp.Width, y);

        pen.DashStyle = DashStyle.Dot;

        float dy = pd + estSize.Height * 0.25f;

        g.DrawLine(pen, 0, dy, bmp.Width, dy);

        //以前景色印上描圖文字

        g.DrawString(txt, GetTraceFont(fs), new SolidBrush(fc), new PointF(pd, pd));

        //將結果以PNG格式傳回

        context.Response.ContentType = "image/png";

        bmp.Save(context.Response.OutputStream, ImageFormat.Png);

    }

    public bool IsReusable { get { return false; } }

}