C#.NET把文字动态生成到图片上。

背景：我需要做一个动态名片。背景图固定，把名字或其他区域的字，动态换

然后生成一张新图，

这是后台.CS类

有哪里不懂留言一起研究

using System;
using System.Collections;
using System.Collections.Generic;
using System.Configuration;
using System.Data;
using System.Drawing;
using System.Drawing.Imaging;
using System.IO;
using System.Net;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;

public partial class aTest : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            //画布的宽度和高度
            int initialWidth = 399, initialHeight = 283;
            Bitmap theBitmap = new Bitmap(initialWidth, initialHeight);
            Graphics theGraphics = Graphics.FromImage(theBitmap);
            //呈现质量
            theGraphics.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;
            //背景色
            theGraphics.Clear(Color.FromArgb(255, 255, 255));
            //灰色边框
            theGraphics.DrawRectangle(new Pen(Color.FromArgb(227, 227, 227), 1), 1, 1, initialWidth - 2,
                initialHeight - 2);

            int autoHeight = 0; //累计高度（动态的内容高度位置）
            int sjh = 0; //时间轴的高度
            float fwigth = 0;
            int fontHeight = 12; //文字行间距
            string FontType = "微软雅黑";
            string IconType = "iconfont";
            Font theFont = new Font(FontType, 12.0f, System.Drawing.FontStyle.Bold);

            //准备工作。定义画刷颜色
            Color col = Color.FromArgb(51, 51, 51);
            Brush newBrush = new SolidBrush(col);
            Brush bush = new SolidBrush(Color.FromArgb(204, 204, 204)); //填充的颜色

            Bitmap bmp = Get_img(@"http://localhost:2446/aadmin/images/zhengshu.jpg");//背景图片地址~/aadmin/images/zhengshu.jpg
            //画布的开始坐标和结束坐标
            theGraphics.DrawImage(bmp, new System.Drawing.Rectangle(0, 0, 399, 283),
            new System.Drawing.Rectangle(0, 0, bmp.Width, bmp.Height),
                            System.Drawing.GraphicsUnit.Pixel);
            //文字居画布的位置坐标
            theGraphics.DrawString("动态文字", theFont, newBrush, 90, 50);

//浏览器自动下载开始
            Response.ContentType = "application/x-msdownload";
            //Bitmap theBitmap = new Bitmap(initialWidth, initialHeight);//此为所画的图片
            string filename = "attachment; filename=001.jpg";
            Response.AddHeader("Content-Disposition", filename);
//浏览器自动下载结束


            //Bitmap转byte[]
            MemoryStream ms = new MemoryStream();
            theBitmap.Save(ms, System.Drawing.Imaging.ImageFormat.Bmp);
            byte[] bytes = ms.GetBuffer();
            ms.Close();

            Response.BinaryWrite(bytes);

            
            string imurl = "/aadmin/userImages/" + DateTime.Now.ToFileTime().ToString() + ".Png";
            MemoryStream stream = new MemoryStream(bytes);
            System.Drawing.Image img = System.Drawing.Image.FromStream(stream);
            //要存到相对路径要用HttpContext.Current.Server.MapPath。否则只能用绝对路径，E:/这种格式
            img.Save(HttpContext.Current.Server.MapPath(imurl), System.Drawing.Imaging.ImageFormat.Png);








        }


    }

    public Bitmap Get_img(string imgurl)
    {
        Bitmap img = null;
        HttpWebRequest req;
        HttpWebResponse res = null;
        try
        {
            System.Uri httpUrl = new System.Uri(imgurl);
            req = (HttpWebRequest)(WebRequest.Create(httpUrl));
            req.Timeout = 180000; //设置超时值10秒
            req.UserAgent = "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:18.0) Gecko/20100101 Firefox/18.0";
            req.Accept = "text/html, application/xhtml+xml, */*";
            req.Method = "GET";
            res = (HttpWebResponse)(req.GetResponse());
            img = new Bitmap(res.GetResponseStream());//获取图片流    
            //string imurl = "~/aadmin/userImages/" + DateTime.Now.ToFileTime().ToString() + ".png";
            //img.Save(imurl );//随机名
        }
        catch (Exception e) {
        }
        return img;
    }
    



}