asp.net MVC 在Controller控制器中实现验证码输出功能

 asp.net mvc项目使用到验证码，为了让以前的webform代码能利用上代码经过稍微的改动即可使用代码如下：

using system;
using system.collections.generic;
using system.web;
using system.web.mvc;
using system.web.ui;
using system.web.ui.webcontrols;
using system.drawing;
namespace angel.web.controllers
{
  public class checkcodecontroller : controller
  {
    //
    // get: /checkcode/
    public actionresult index()
    {
      this.createcheckcodeimage(generatecheckcode());
      return view();
    }
    private string generatecheckcode()
    {
      int number;
      char code;
      string checkcode = string.empty;
      system.random random = new random();
      for (int i = 0; i < 5; i++)
      {
        number = random.next();
        if (number % 2 == 0)
          code = (char)('0' + (char)(number % 10));
        else
          code = (char)('a' + (char)(number % 26));
        if (code == '0' || code == 'o' || code == 'l' || code == 'i')
        {
          i = i - 1;
        }
        else
        {
          checkcode += code.tostring();
        }
      }
      // response.cookies.add(new httpcookie("checkcode", checkcode));
      session.contents["checkcode"] = checkcode;
      return checkcode;
    }
    private void createcheckcodeimage(string checkcode)
    {
      if (checkcode == null || checkcode.trim() == string.empty)
        return;
      system.drawing.bitmap image = new system.drawing.bitmap((int)math.ceiling((checkcode.length * 12.5)), 22);
      graphics g = graphics.fromimage(image);
      try
      {
        //生成随机生成器
        random random = new random();
        //清空图片背景色
        g.clear(color.white);
        //画图片的背景噪音线
        for (int i = 0; i < 25; i++)
        {
          int x1 = random.next(image.width);
          int x2 = random.next(image.width);
          int y1 = random.next(image.height);
          int y2 = random.next(image.height);
          g.drawline(new pen(color.silver), x1, y1, x2, y2);
        }
        font font = new system.drawing.font("arial", 12, (system.drawing.fontstyle.bold | system.drawing.fontstyle.italic));
        system.drawing.drawing2d.lineargradientbrush brush = new system.drawing.drawing2d.lineargradientbrush(new rectangle(0, 0, image.width, image.height), color.blue, color.darkred, 1.2f, true);
        g.drawstring(checkcode, font, brush, 2, 2);
        //画图片的前景噪音点
        for (int i = 0; i < 100; i++)
        {
          int x = random.next(image.width);
          int y = random.next(image.height);
          image.setpixel(x, y, color.fromargb(random.next()));
        }
        //画图片的边框线
        g.drawrectangle(new pen(color.silver), 0, 0, image.width - 1, image.height - 1);
        system.io.memorystream ms = new system.io.memorystream();
        image.save(ms, system.drawing.imaging.imageformat.gif);
        response.clearcontent();
        response.contenttype = "image/gif";
        response.binarywrite(ms.toarray());
      }
      finally
      {
        g.dispose();
        image.dispose();
      }
    }
  }
}

　　最后别忘了session的获取设置，需要在global.asax.cs文件中新增如下代码：

/// <summary>
/// mvc为了获取session参数
/// </summary>
public override void init()
{
  postauthenticaterequest += (s, e) => httpcontext.current.setsessionstatebehavior(sessionstatebehavior.required);
  base.init();
}
void mvcapplication_postauthenticaterequest(object sender, eventargs e)
{
  httpcontext.current.setsessionstatebehavior(sessionstatebehavior.required);
}

html页面代码：

html代码

<img name="img1" id="img1" style="position:absolute;top:5px;right:36px!important;z-index:1000;" alt="单击图片刷新验证码" src="checkcode/index" <br>onclick="javasccript:reloadimage('checkcode/index');" /><br><script type="text/javascript">
function reloadimage(url) {
document.getelementbyid("img1").src = url + '?abc=' + math.random();
}
  </script>

总结

以上所述是小编给大家介绍的asp.net mvc 在controller控制器中实现验证码输出功能，希望对大家有所帮助