using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

using System.Web;
using System.IO;
using NVelocity.App;
using NVelocity;
using NVelocity.Runtime;

namespace Common
{
public class NVelocityHelper
{
private VelocityEngine velocityEngine = null;
private VelocityContext vc = null;
public NVelocityHelper(string templatePath, string key, object value)
{

//1.创建Velocity 引擎（VelocityEngine）并设置属性
velocityEngine = new VelocityEngine();
velocityEngine.AddProperty(RuntimeConstants.RESOURCE_LOADER, "file"); // Velocity加载类型
velocityEngine.AddProperty(RuntimeConstants.FILE_RESOURCE_LOADER_PATH, // Velocity加载文件路径
HttpContext.Current.Server.MapPath("~/" + templatePath + "/"));
velocityEngine.AddProperty(RuntimeConstants.INPUT_ENCODING, "utf-8"); // 输入编码格式设置
velocityEngine.AddProperty(RuntimeConstants.OUTPUT_ENCODING, "utf-8"); // 输出编码格式设置
velocityEngine.Init();
//2.Velocity 上下文对象设置
vc = new VelocityContext();
vc.Put(key, value);
}

public NVelocityHelper(string key, object value)
{
//1.创建Velocity 引擎（VelocityEngine）并设置属性
velocityEngine = new VelocityEngine();
velocityEngine.AddProperty(RuntimeConstants.RESOURCE_LOADER, "file"); // Velocity加载类型
velocityEngine.AddProperty(RuntimeConstants.FILE_RESOURCE_LOADER_PATH, // Velocity加载文件路径
HttpContext.Current.Server.MapPath("~/Templates/"));
velocityEngine.AddProperty(RuntimeConstants.INPUT_ENCODING, "utf-8"); // 输入编码格式设置
velocityEngine.AddProperty(RuntimeConstants.OUTPUT_ENCODING, "utf-8"); // 输出编码格式设置
velocityEngine.Init();
//2.Velocity 上下文对象设置
vc = new VelocityContext();
vc.Put(key, value);
}

public void Render(string templatFileName)
{
//3.创建模板
Template template = velocityEngine.GetTemplate(templatFileName);

//4.合并模板和上下文对象、输出
StringWriter writer = new StringWriter();
template.Merge(vc, writer);
HttpContext.Current.Response.Write(writer.ToString());
HttpContext.Current.Response.End();
}

}
}