1.在Action处理之后,必须有一个返回值,这个返回值必须继承自ActionResult的对象

2.ActionResult,实际就是服务器端响应给客户端的结果

  • ViewResult(返回视图结果)
  • FileResult(二进制文件相应给客户端),FileContentResult继承自FileResult
  • ContentResult(将内容相应给客户端)
  • JsonResult(将对象传递给客户端)
  • JavaScriptResult(将一段JavaScript脚本传递给客户端)
  • PartiaView(返回分布视图)

FileContentResult的应用案例

做一个验证码图片

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Drawing;
using System.IO;
using System.Drawing.Drawing2D;
using System.Drawing.Imaging;

namespace MvcBookShop.Common
{
    public class ValidateCode
    {
        /// <summary>
        /// 生成验证码
        /// </summary>
        /// <param name="length">指定验证码的长度</param>
        /// <returns></returns>
        public string CreateValidateCode(int length)
        {
            int[] randMembers = new int[length];
            int[] validateNums = new int[length];
            string validateNumberStr = "";
            //生成起始序列值
            int seekSeek = unchecked((int)DateTime.Now.Ticks);
            Random seekRand = new Random(seekSeek);
            int beginSeek = (int)seekRand.Next(0, Int32.MaxValue - length * 10000);
            int[] seeks = new int[length];
            for (int i = 0; i < length; i++)
            {
                beginSeek += 10000;
                seeks[i] = beginSeek;
            }
            //生成随机数字
            for (int i = 0; i < length; i++)
            {
                Random rand = new Random(seeks[i]);
                int pownum = 1 * (int)Math.Pow(10, length);
                randMembers[i] = rand.Next(pownum, Int32.MaxValue);
            }
            //抽取随机数字
            for (int i = 0; i < length; i++)
            {
                string numStr = randMembers[i].ToString();
                int numLength = numStr.Length;
                Random rand = new Random();
                int numPosition = rand.Next(0, numLength - 1);
                validateNums[i] = Int32.Parse(numStr.Substring(numPosition, 1));
            }
            //生成验证码
            for (int i = 0; i < length; i++)
            {
                validateNumberStr += validateNums[i].ToString();
            }
            return validateNumberStr;
        }

        /// <summary>
        /// 创建验证码的图片
        /// </summary>
        /// <param name="containsPage">要输出到的page对象</param>
        /// <param name="validateNum">验证码</param>
        public byte[] CreateValidateGraphic(string validateCode)
        {
            Bitmap image = new Bitmap((int)Math.Ceiling(validateCode.Length * 12.0), 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);
                //画图片的干扰线
                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 Font("Arial", 12, (FontStyle.Bold | FontStyle.Italic));
                LinearGradientBrush brush = new LinearGradientBrush(new Rectangle(0, 0, image.Width, image.Height),
                 Color.Blue, Color.DarkRed, 1.2f, true);
                g.DrawString(validateCode, font, brush, 3, 2);
                //画图片的前景干扰点
                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);
                //保存图片数据
                MemoryStream stream = new MemoryStream();
                image.Save(stream, ImageFormat.Jpeg);
                //输出图片流
                return stream.ToArray();
            }
            finally
            {
                g.Dispose();
                image.Dispose();
            }
        }
    }
}

ValidateCode

 

//创建图片验证码
        public ActionResult ValidateImage()
        {
         ValidateCode validateCode=new ValidateCode ();
            string strCode=validateCode.CreateValidateCode(5);
            Session["validateCode"]=strCode;
            Byte[] ImageCode=validateCode.CreateValidateGraphic(strCode);
            return File(ImageCode, @"image/gif");//类似于Content-Type,表示服务器响应给服务器端的类型
        }
//表示返回的是FileContentResult对象,ImageCode表示一个二进制的字节数组,@"image/gif"表示服务器相应给客户端的二进制文件类型。

JsonResult案例,实际是把对象序列化后发给客户端。(这个对象一定要重新构建对象的序列图,实际就是需要new一个新的对象出来)

在用户登陆之后鼠标移动在上面有个悬浮窗显示用户的基本信息

<div id="userinfo" style="display:none">
            <table border="1">
                <tr>
                    <th>
                        用户名
                    </th>
                    <th>
                        地址
                    </th>
                    <th>
                        电话
                    </th>
                </tr>
                <tr>
                    <td id="Name">
                        
                    </td>
                    <td id="Address">
                        
                    </td>
                    <td id="Phone">
                        
                    </td>
                </tr>
            </table>
            </div>

悬浮层div代码

<script language="javascript" type="text/javascript">
        $(function () {
            $.get(("/User/ShowUser"), null, function (data) {
                if (data != "0") {
                    $("#loginUser").text(data).attr("href", "#").attr("iflogin", "true");
                }
            }, "text");

            $("#loginUser").mouseover(function () {

                if ($(this).attr("iflogin")) {
                    $.post("/User/GetUserInfo", null, function (data) {
                        $("#Name").html(data.Name);
                        $("#Address").html(data.Address);
                        $("#Phone").html(data.Phone);
                        $("#userinfo").css("display", "block");
                    }, "json");
                } else {
                    $(this).unbind("mouseover"); //将某个事件操作移除
                }
            }).mouseout(function () {
                $("#userinfo").css("display", "none");
            });

        });
    </script>

js代码

public ActionResult ShowUser()
        {
            ContentResult content = new ContentResult();
            if (Session["User"] == null)
            {
                content.Content = "0";
            }
            else
            {
                content.Content = (Session["User"] as MvcBookShop.Models.User).Name;
            }
            return content;
        }
        [HttpPost]
        public ActionResult GetUserInfo()
        {
            JsonResult js = new JsonResult();
            MvcBookShop.Models.User user = Session["User"] as MvcBookShop.Models.User;
            //构建新的对象序列图,必须要new
            var obj = new
            {
                    Name=user.Name,
                    Address=user.Address,
                    Phone=user.Phone
            };
            js.Data = obj;
            //如果这个请求非要是get请求那么需要加下面这段代码
            //js.JsonRequestBehavior = JsonRequestBehavior.AllowGet; //允许来自客户端的get请求
            return js;
        }

 

注意:在请求JsonResult对象返回的时候,一般默认都采用Post方式请求,如果非要get方式请求,需要去加一段代码:设置:JsonRequestBehavior属性值为:JsonRequestBehavior.AllowGet;

[HttpGet]
        public ActionResult GetUserInfo()
        {
            JsonResult js = new JsonResult();
            MvcBookShop.Models.User user = Session["User"] as MvcBookShop.Models.User;
            //构建新的对象序列图,必须要new
            var obj = new
            {
                    Name=user.Name,
                    Address=user.Address,
                    Phone=user.Phone
            };
            js.Data = obj;
            //如果这个请求非要是get请求那么需要加下面这段代码
            js.JsonRequestBehavior = JsonRequestBehavior.AllowGet; //允许来自客户端的get请求
            return js;
        }

Get请求时的代码写法