标签：exception att time isnull temp attach sum encode idt
后台代码：
using BLL;
using NPOI.HSSF.UserModel;
using NPOI.SS.UserModel;
using System;
using System.Collections.Generic;
using System.Data;
using System.IO;
using System.IO.MemoryMappedFiles;
using System.Linq;
using System.Web;
using System.Web.UI;
namespace EasyUI
{
/// <summary>
/// ExcelHandler 的摘要说明
/// </summary>
public class ExcelHandler : IHttpHandler
{
public void ProcessRequest(HttpContext context)
{
try
{
DataTable dt = new DataTable();
dt = Service.Excel();//数据源
string strFileName = "Excel";
//创建空excel文件
HSSFWorkbook workbook = new HSSFWorkbook();
ISheet sheet = string.IsNullOrEmpty(strFileName) ? workbook.CreateSheet("Sheet1") : workbook.CreateSheet(strFileName);
//表头
IRow row = sheet.CreateRow(0);
for (int i = 0; i < dt.Columns.Count; i++)
{
ICell cell = row.CreateCell(i);
cell.SetCellValue(dt.Columns[i].ColumnName);
//创建列头的样式
HSSFCellStyle cellStyle = (HSSFCellStyle)workbook.CreateCellStyle();
//居中显示
cellStyle.Alignment = HorizontalAlignment.Center;
//垂直居中
cellStyle.VerticalAlignment = VerticalAlignment.Center;
HSSFFont font = (HSSFFont)workbook.CreateFont();
font.FontHeightInPoints = 12;
font.FontName = "宋体";
font.IsBold = true;
cellStyle.SetFont(font);
cell.CellStyle = cellStyle;
}
//数据
int[] len = new int[dt.Columns.Count];
for (int i = 0; i < dt.Rows.Count; i++)
{
//行
IRow rows = sheet.CreateRow(i + 1);
for (int j = 0; j < dt.Columns.Count; j++)
{
//列
ICell cell = rows.CreateCell(j);
cell.SetCellValue(dt.Rows[i][j].ToString());
var lenTemp = dt.Rows[i][j].ToString().Length > dt.Columns[j].ColumnName.Length ? dt.Rows[i][j].ToString().Length : dt.Columns[j].ColumnName.Length;
if (lenTemp > len[j])
{
len[j] = lenTemp;
}
}
}
//自动设置列宽
for (int i = 0; i < len.Length; i++)
{
if (len[i] < 8)
{
len[i] = Convert.ToInt32(Math.Round(len[i] * 2.5));
}
else
{
len[i] = Convert.ToInt32(Math.Round(len[i] * 1.3));
}
sheet.SetColumnWidth(i, len[i] * 256);
}
string fileName = strFileName + DateTime.Now.ToString("yyMMddHHmmssfff") + ".xls";
//写入到客户端
MemoryStream ms = new MemoryStream(); //创建其支持存储区为内存的流
//数据写入流中
workbook.Write(ms);
// 设置当前流的位置为流的开始
ms.Seek(0, SeekOrigin.Begin);
//防止中文乱码
fileName = HttpUtility.UrlEncode(fileName);
//设置输出编码格式
//context.Response.ContentEncoding = System.Text.Encoding.UTF8;
//设置输出流
context.Response.ContentType = "application/vnd.ms-excel";
//// 限制类型
//context.Response.AddHeader("content-type", "application/vnd.ms-excel");
//下载后文件名
context.Response.AddHeader("Content-Disposition", "attachment;filename=" + System.Web.HttpUtility.UrlEncode(fileName, System.Text.Encoding.UTF8));
workbook = null;
ms.Close();
ms.Dispose();
//实现文件下载
context.Response.BinaryWrite(ms.ToArray());
}
catch (Exception ex)
{
context.Response.Write(ex.Message);
}
//ExportDataSetToExcel(dt, fileName, "sheet1");
}
public bool IsReusable
{
get
{
return false;
}
}
}
}
返回前台后： window.open("ExcelHandler.ashx");//打开浏览器窗口
别忘记在项目中引用NPOI
数据导入Excel表格
标签：exception att time isnull temp attach sum encode idt
原文地址：https://www.cnblogs.com/-zzc/p/9603594.html
