C#使用NPOI跨域生成excel文件并且下载例子

1、服务端，根据参数获取数据数据

 引用dll：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Services;
using NPOI.HSSF.UserModel;
using NPOI.HPSF;
using NPOI.POIFS.FileSystem;
using NPOI.SS.UserModel;
using NPOI.SS.Formula.Functions;
using System.IO;

初始化NPOI的实体：

HSSFWorkbook hssfworkbook;
        void InitializeWorkbook()
        {
            hssfworkbook = new HSSFWorkbook();
            ////create a entry of DocumentSummaryInformation
            DocumentSummaryInformation dsi = PropertySetFactory.CreateDocumentSummaryInformation();
            dsi.Company = "AP分析";
            hssfworkbook.DocumentSummaryInformation = dsi;
            ////create a entry of SummaryInformation
            SummaryInformation si = PropertySetFactory.CreateSummaryInformation();
            si.Subject = "导出分析结果";
            hssfworkbook.SummaryInformation = si;
}
设置表头和数据对应：

private string Pengzhuang(int taskid, int tasktype)
        {
            string url = "";
            AP.BLL.CrashResult crashbll = new AP.BLL.CrashResult();
            List list = crashbll.GetModelList(" TaskID=" + taskid);
            int count = 0;
            //用npoi先写表头
            InitializeWorkbook();
            ISheet sheet1 = hssfworkbook.CreateSheet("任务" + taskid + "导出结果");
            IRow row1 = sheet1.CreateRow(0);
            row1.CreateCell(0).SetCellValue("序号");
            row1.CreateCell(1).SetCellValue("Mac");
            row1.CreateCell(2).SetCellValue("碰撞率");
            int x = 1;
            foreach (AP.Model.CrashResult cs in list)
            {
                IRow row = sheet1.CreateRow(x);
                row.CreateCell(0).SetCellValue(cs.ID);
                row.CreateCell(1).SetCellValue(cs.Mac);
                row.CreateCell(2).SetCellValue(cs.CrashCount.ToString());
                x++;
            }
            url = WriteToFile();
            return url;
        }
返回文件下载的url：

[WebMethod]
        public void Exceldown(int taskid,int tasktype)
        {
            string url = "";
            switch(tasktype)
            {
                case 2://
                    url = Pengzhuang(taskid,tasktype);
                    break;
               
                default:
                    url = "#";
                    break;
            }
            CheckResponse.SendResponse(url);
}

文件生成：

string WriteToFile()
        {
            //Write the stream data of workbook to the root directory
            string serverImagePath = "cardxls";
            string filename = hssfworkbook.GetSheetAt(0).SheetName + ".xls";
            string temppath = System.Web.HttpContext.Current.Server.MapPath(serverImagePath);
            if (!Directory.Exists(temppath))
            {
                Directory.CreateDirectory(temppath);
            }
            FileStream file = new FileStream(System.Web.HttpContext.Current.Server.MapPath(serverImagePath + "/" + filename), FileMode.Create);
            hssfworkbook.Write(file);
            file.Close();
            return "/" + serverImagePath + "/" + filename;
}

2、js ajax调用服务

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="FileDown.aspx.cs" Inherits="Ap.Service.FileDown" %>




   


   

   
    
       

            正在生成文件，请稍等......