【ASP.NET】C# 将HTML中Table导出到Excel（TableToExcel）

　　首先，说下应用场景 就是，把页面呈现的Table 导出到Excel中。其中使用的原理是 前台使用ajax调用aspx后台，传递过去参数值，导出。使用的组件是NPOI。

　　前台调用：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

using NPOI.HSSF.UserModel;
using NPOI.HPSF;
using NPOI.POIFS.FileSystem;
using NPOI.HSSF.Util;
using System.Text.RegularExpressions;
using System.IO;

namespaceDemo
{
public partial class TableToExcel : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
string act = GetValue("act");

//toExcel.aspx?act=tabletoexcel&html=<table class="reportstable">..</table>
if (act == "tabletoexcel")
{
TableToExcelMethod();
}
}
public void TableToExcelMethod()
{
string tableHtml = Request.Form["html"];    //接受前台table 数值字符串
if (string.IsNullOrEmpty(tableHtml)) { return; }

InitializeWorkbook();
HSSFSheet sheet1 = (HSSFSheet)hssfworkbook.CreateSheet("Sheet1");

string rowContent = string.Empty;
MatchCollection rowCollection = Regex.Matches(tableHtml, @"<tr[^>]*>[\s\S]*?<\/tr>",
RegexOptions.IgnoreCase | RegexOptions.ExplicitCapture); //对tr进行筛选

NPOI.SS.UserModel.IFont fontSubTitle = hssfworkbook.CreateFont();
fontSubTitle.Boldweight = 800;//加粗

NPOI.SS.UserModel.IFont fontBody = hssfworkbook.CreateFont();
fontBody.Boldweight = 500;//加粗

for (int i = 0; i < rowCollection.Count; i++)
{
HSSFRow row = (HSSFRow)sheet1.CreateRow(i);
rowContent = rowCollection[i].Value;

MatchCollection columnCollection = Regex.Matches(rowContent, @"<th[^>]*>[\s\S]*?<\/th>",
RegexOptions.IgnoreCase | RegexOptions.ExplicitCapture); //对td进行筛选
for (int td = 0; td < columnCollection.Count; td++)
{
row.CreateCell(td).SetCellValue(HtmlToTxt(columnCollection.Value));
}

columnCollection = Regex.Matches(rowContent, @"<td[^>]*>[\s\S]*?<\/td>",
RegexOptions.IgnoreCase | RegexOptions.ExplicitCapture); //对td进行筛选
for (int td = 0; td < columnCollection.Count; td++)
{
row.CreateCell(td).SetCellValue(HtmlToTxt(columnCollection.Value));
}
}
WriteToFile();
downFile(ppath);
}

static HSSFWorkbook hssfworkbook;
public string ppath;

public void WriteToFile()
{
string year = DateTime.Now.Year.ToString();
ppath = HttpContext.Current.Server.MapPath(DateTime.Now.ToString("yyyyMMddmmss") + ".xls");
FileStream file = new FileStream(ppath, FileMode.Create);
hssfworkbook.Write(file);
file.Close();
}

public void InitializeWorkbook()
{
hssfworkbook = new HSSFWorkbook();
////create a entry of DocumentSummaryInformation
DocumentSummaryInformation dsi = PropertySetFactory.CreateDocumentSummaryInformation();
dsi.Company = "company";
hssfworkbook.DocumentSummaryInformation = dsi;
////create a entry of SummaryInformation
SummaryInformation si = PropertySetFactory.CreateSummaryInformation();
si.Subject = "xxx";
hssfworkbook.SummaryInformation = si;
}

public void downFile(string ppath)
{
if (File.Exists(ppath))
{
Response.ClearHeaders();
Response.Clear();
Response.Expires = 0;
Response.Buffer = true;
Response.AddHeader("Accept-Language", "zh-cn");
string name = System.IO.Path.GetFileName(ppath);
System.IO.FileStream files = new FileStream(ppath, FileMode.Open, FileAccess.Read, FileShare.Read);
byte[] byteFile = null;
if (files.Length == 0)
{
byteFile = new byte[1];
}
else
{
byteFile = new byte[files.Length];
}
files.Read(byteFile, 0, (int)byteFile.Length);
files.Close();
File.Delete(files.Name);
Response.AddHeader("Content-Disposition", "attachment;filename=" + HttpUtility.UrlEncode(name, System.Text.Encoding.UTF8));
Response.ContentType = "application/octet-stream;charset=gbk";
Response.BinaryWrite(byteFile);
Response.End();
}
}

/// <summary>
/// POST/GET 参数获取
/// </summary>
/// <param name="context"></param>
/// <param name="name"></param>
/// <returns></returns>
private string GetValue(string name)
{
string result = ConvertToString(Request.QueryString[name], "");
if (string.IsNullOrEmpty(result))
{
result = ConvertToString(Request.Form[name], "");
}
return FilterSpecial(result);
}

public static string ConvertToString(Object obj, string strDefault)
{
try
{
if (obj == null)
{
return strDefault;
}
return obj.ToString();
}
catch
{
}
return strDefault;
}

/// <summary>
/// HTML转行成TEXT
/// </summary>
/// <param name="strHtml"></param>
/// <returns></returns>
public static string HtmlToTxt(string strHtml)
{
string[] aryReg ={
@"<script[^>]*?>.*?</script>",
@"<(\/\s*)?!?((\w+:)?\w+)(\w+(\s*=?\s*(([""'])(\\[""'tbnr]|[^\7])*?\7|\w+)|.{0})|\s)*?(\/\s*)?>",
@"([\r\n])[\s]+",
@"&(quot|#34);",
@"&(amp|#38);",
@"&(lt|#60);",
@"&(gt|#62);",
@"&(nbsp|#160);",
@"&(iexcl|#161);",
@"&(cent|#162);",
@"&(pound|#163);",
@"&(copy|#169);",
@"&#(\d+);",
@"-->",
@"<!--.*\n"
};
string newReg = aryReg[0];
string strOutput = strHtml;
for (int i = 0; i < aryReg.Length; i++)
{
Regex regex = new Regex(aryReg[i], RegexOptions.IgnoreCase);
strOutput = regex.Replace(strOutput, string.Empty);
}
strOutput.Replace("<", "");
strOutput.Replace(">", "");
strOutput.Replace("\r\n", "");
return strOutput;
}

/// <summary>
/// 过滤特殊字符
/// 如果字符串为空，直接返回。
/// </summary>
/// <param name="str">需要过滤的字符串</param>
/// <returns>过滤好的字符串</returns>
public static string FilterSpecial(string str)
{
if (str == "")
{
return str;
}
else
{
str = str.Replace("'", "");
str = str.Replace("<", "");
str = str.Replace(">", "");
str = str.Replace("%", "");
str = str.Replace("'delete", "");
str = str.Replace("''", "");
str = str.Replace("\"\"", "");
str = str.Replace(",", "");
str = str.Replace(".", "");
str = str.Replace(">=", "");
str = str.Replace("=<", "");
str = str.Replace("-", "");
str = str.Replace("_", "");
str = str.Replace(";", "");
str = str.Replace("||", "");
str = str.Replace("[", "");
str = str.Replace("]", "");
str = str.Replace("&", "");
str = str.Replace("#", "");
str = str.Replace("/", "");
str = str.Replace("-", "");
str = str.Replace("|", "");
str = str.Replace("?", "");
str = str.Replace(">?", "");
str = str.Replace("?<", "");
str = str.Replace(" ", "");
return str;
}
}
}
}

View Code
　　附上NPOI的DLL下载地址： 点 击 下 载

　　最后，整体来说能够导出table到excel，但是同时存在一个问题，就是 导出后没有table的样式。