自定义 httpHandlers

1、在<system.web>下配置

<httpHandlers>
   <add verb="GET,HEAD" path="*.vm" type="NVelocityHandler" validate="false" />
  </httpHandlers>

2、创建 NVelocityHandler类，代码如下：

 

using System;
using System.Collections.Generic;
using System.IO;
using System.Web;
using Commons.Collections;
using NVelocity.App;
using NVelocity.Context;
using NVelocity.Runtime;
using NVelocity;

/**/
/// <summary>
/// 
/// </summary>
public class NVelocityHandler : IHttpHandler
{
    IHttpHandler Members;

    public bool IsReusable
    {
        get { return false; }
    }

    public void ProcessRequest(HttpContext context)
    {
        // context.Response.Write("测试数据");
        VelocityEngine velocity = new VelocityEngine();

        ExtendedProperties props = new ExtendedProperties();

        //定义模板路径
        props.SetProperty(RuntimeConstants.FILE_RESOURCE_LOADER_PATH, context.Server.MapPath(""));

        //初始化
        velocity.Init(props);

        List<City> list = new List<City>();

        list.Add(new City(21, "sh"));
        list.Add(new City(22, "bj"));
        list.Add(new City(23, "tj"));


        IContext c = new VelocityContext();

        //添加到上下文中
        c.Put("cities", list);

        //根据请求输出
        velocity.MergeTemplate("Template/test.vm", "UTF-8", c, context.Response.Output);

    }
}

/**/
/// <summary>
/// 城市
/// </summary>
public class City
{

    public City(int id, string name)
    {
        this.id = id;
        this.name = name;
    }
    private int id;

    public int Id
    {
        get { return id; }
        set { id = value; }
    }
    /**/
    /// <summary>
    /// 名称
    /// </summary>
    private string name;

    public string Name
    {
        get { return name; }
        set { name = value; }
    }
}

 

3、test.vm在根目录下，其了内容如下：

1##循环输出
2#foreach($city in $cities)
3Id:$city.id<br />
4城市名称:$city.name<br />
5#end
6##索引获取数据
7$cities.get_item(2).name

4、项目中需要引用NVelocity.dll

5、运行项目输入http://主机名/项目名/test.vm 你会惊奇的发现显示的效果。