C#自定义导出数据到Excel的类实例

using System;
using System.IO;
using System.Data;
using System.Collections;
using System.Data.OleDb;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
namespace DotNet.Utilities
{
  /// <summary>
  /// Excel操作类
  /// </summary>
  /// Microsoft Excel 11.0 Object Library
  public class ExcelHelper
  {
    #region 数据导出至Excel文件
    /// </summary>
    /// 导出Excel文件，自动返回可下载的文件流
    /// </summary>
    public static void DataTable1Excel(System.Data.DataTable dtData)
    {
      GridView gvExport = null;
      HttpContext curContext = HttpContext.Current;
      StringWriter strWriter = null;
      HtmlTextWriter htmlWriter = null;
      if (dtData != null)
      {
        curContext.Response.ContentType = "application/vnd.ms-excel";
        curContext.Response.ContentEncoding = System.Text.Encoding.GetEncoding("gb2312");
        curContext.Response.Charset = "utf-8";
        strWriter = new StringWriter();
        htmlWriter = new HtmlTextWriter(strWriter);
        gvExport = new GridView();
        gvExport.DataSource = dtData.DefaultView;
        gvExport.AllowPaging = false;
        gvExport.DataBind();
        gvExport.RenderControl(htmlWriter);
        curContext.Response.Write("<meta http-equiv=\"Content-Type\" content=\"text/html;charset=gb2312\"/>" + strWriter.ToString());
        curContext.Response.End();
      }
    }
    /// <summary>
    /// 导出Excel文件，转换为可读模式
    /// </summary>
    public static void DataTable2Excel(System.Data.DataTable dtData)
    {
      DataGrid dgExport = null;
      HttpContext curContext = HttpContext.Current;
      StringWriter strWriter = null;
      HtmlTextWriter htmlWriter = null;
      if (dtData != null)
      {
        curContext.Response.ContentType = "application/vnd.ms-excel";
        curContext.Response.ContentEncoding = System.Text.Encoding.UTF8;
        curContext.Response.Charset = "";
        strWriter = new StringWriter();
        htmlWriter = new HtmlTextWriter(strWriter);
        dgExport = new DataGrid();
        dgExport.DataSource = dtData.DefaultView;
        dgExport.AllowPaging = false;
        dgExport.DataBind();
        dgExport.RenderControl(htmlWriter);
        curContext.Response.Write(strWriter.ToString());
        curContext.Response.End();
      }
    }
    /// <summary>
    /// 导出Excel文件，并自定义文件名
    /// </summary>
    public static void DataTable3Excel(System.Data.DataTable dtData, String FileName)
    {
      GridView dgExport = null;
      HttpContext curContext = HttpContext.Current;
      StringWriter strWriter = null;
      HtmlTextWriter htmlWriter = null;
      if (dtData != null)
      {
        HttpUtility.UrlEncode(FileName, System.Text.Encoding.UTF8);
        curContext.Response.AddHeader("content-disposition", "attachment;filename=" + HttpUtility.UrlEncode(FileName, System.Text.Encoding.UTF8) + ".xls");
        curContext.Response.ContentType = "application nd.ms-excel";
        curContext.Response.ContentEncoding = System.Text.Encoding.UTF8;
        curContext.Response.Charset = "GB2312";
        strWriter = new StringWriter();
        htmlWriter = new HtmlTextWriter(strWriter);
        dgExport = new GridView();
        dgExport.DataSource = dtData.DefaultView;
        dgExport.AllowPaging = false;
        dgExport.DataBind();
        dgExport.RenderControl(htmlWriter);
        curContext.Response.Write(strWriter.ToString());
        curContext.Response.End();
      }
    }
    /// <summary>
    /// 将数据导出至Excel文件
    /// </summary>
    /// <param name="Table">DataTable对象</param>
    /// <param name="ExcelFilePath">Excel文件路径</param>
    public static bool OutputToExcel(DataTable Table, string ExcelFilePath)
    {
      if (File.Exists(ExcelFilePath))
      {
        throw new Exception("该文件已经存在！");
      }
      if ((Table.TableName.Trim().Length == 0) || (Table.TableName.ToLower() == "table"))
      {
        Table.TableName = "Sheet1";
      }
      //数据表的列数
      int ColCount = Table.Columns.Count;
      //用于记数，实例化参数时的序号
      int i = 0;
      //创建参数
      OleDbParameter[] para = new OleDbParameter[ColCount];
      //创建表结构的SQL语句
      string TableStructStr = @"Create Table " + Table.TableName + "(";
      //连接字符串
      string connString = @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + ExcelFilePath + ";Extended Properties=Excel 8.0;";
      OleDbConnection objConn = new OleDbConnection(connString);
      //创建表结构
      OleDbCommand objCmd = new OleDbCommand();
      //数据类型集合
      ArrayList DataTypeList = new ArrayList();
      DataTypeList.Add("System.Decimal");
      DataTypeList.Add("System.Double");
      DataTypeList.Add("System.Int16");
      DataTypeList.Add("System.Int32");
      DataTypeList.Add("System.Int64");
      DataTypeList.Add("System.Single");
      //遍历数据表的所有列，用于创建表结构
      foreach (DataColumn col in Table.Columns)
      {
        //如果列属于数字列，则设置该列的数据类型为double
        if (DataTypeList.IndexOf(col.DataType.ToString()) >= 0)
        {
          para[i] = new OleDbParameter("@" + col.ColumnName, OleDbType.Double);
          objCmd.Parameters.Add(para[i]);
          //如果是最后一列
          if (i + 1 == ColCount)
          {
            TableStructStr += col.ColumnName + " double)";
          }
          else
          {
            TableStructStr += col.ColumnName + " double,";
          }
        }
        else
        {
          para[i] = new OleDbParameter("@" + col.ColumnName, OleDbType.VarChar);
          objCmd.Parameters.Add(para[i]);
          //如果是最后一列
          if (i + 1 == ColCount)
          {
            TableStructStr += col.ColumnName + " varchar)";
          }
          else
          {
            TableStructStr += col.ColumnName + " varchar,";
          }
        }
        i++;
      }
      //创建Excel文件及文件结构
      try
      {
        objCmd.Connection = objConn;
        objCmd.CommandText = TableStructStr;
        if (objConn.State == ConnectionState.Closed)
        {
          objConn.Open();
        }
        objCmd.ExecuteNonQuery();
      }
      catch (Exception exp)
      {
        throw exp;
      }
      //插入记录的SQL语句
      string InsertSql_1 = "Insert into " + Table.TableName + " (";
      string InsertSql_2 = " Values (";
      string InsertSql = "";
      //遍历所有列，用于插入记录，在此创建插入记录的SQL语句
      for (int colID = 0; colID < ColCount; colID++)
      {
        if (colID + 1 == ColCount) //最后一列
        {
          InsertSql_1 += Table.Columns[colID].ColumnName + ")";
          InsertSql_2 += "@" + Table.Columns[colID].ColumnName + ")";
        }
        else
        {
          InsertSql_1 += Table.Columns[colID].ColumnName + ",";
          InsertSql_2 += "@" + Table.Columns[colID].ColumnName + ",";
        }
      }
      InsertSql = InsertSql_1 + InsertSql_2;
      //遍历数据表的所有数据行
      for (int rowID = 0; rowID < Table.Rows.Count; rowID++)
      {
        for (int colID = 0; colID < ColCount; colID++)
        {
          if (para[colID].DbType == DbType.Double && Table.Rows[rowID][colID].ToString().Trim() == "")
          {
            para[colID].Value = 0;
          }
          else
          {
            para[colID].Value = Table.Rows[rowID][colID].ToString().Trim();
          }
        }
        try
        {
          objCmd.CommandText = InsertSql;
          objCmd.ExecuteNonQuery();
        }
        catch (Exception exp)
        {
          string str = exp.Message;
        }
      }
      try
      {
        if (objConn.State == ConnectionState.Open)
        {
          objConn.Close();
        }
      }
      catch (Exception exp)
      {
        throw exp;
      }
      return true;
    }
    /// <summary>
    /// 将数据导出至Excel文件
    /// </summary>
    /// <param name="Table">DataTable对象</param>
    /// <param name="Columns">要导出的数据列集合</param>
    /// <param name="ExcelFilePath">Excel文件路径</param>
    public static bool OutputToExcel(DataTable Table, ArrayList Columns, string ExcelFilePath)
    {
      if (File.Exists(ExcelFilePath))
      {
        throw new Exception("该文件已经存在！");
      }
      //如果数据列数大于表的列数，取数据表的所有列
      if (Columns.Count > Table.Columns.Count)
      {
        for (int s = Table.Columns.Count + 1; s <= Columns.Count; s++)
        {
          Columns.RemoveAt(s);  //移除数据表列数后的所有列
        }
      }
      //遍历所有的数据列，如果有数据列的数据类型不是 DataColumn，则将它移除
      DataColumn column = new DataColumn();
      for (int j = 0; j < Columns.Count; j++)
      {
        try
        {
          column = (DataColumn)Columns[j];
        }
        catch (Exception)
        {
          Columns.RemoveAt(j);
        }
      }
      if ((Table.TableName.Trim().Length == 0) || (Table.TableName.ToLower() == "table"))
      {
        Table.TableName = "Sheet1";
      }
      //数据表的列数
      int ColCount = Columns.Count;
      //创建参数
      OleDbParameter[] para = new OleDbParameter[ColCount];
      //创建表结构的SQL语句
      string TableStructStr = @"Create Table " + Table.TableName + "(";
      //连接字符串
      string connString = @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + ExcelFilePath + ";Extended Properties=Excel 8.0;";
      OleDbConnection objConn = new OleDbConnection(connString);
      //创建表结构
      OleDbCommand objCmd = new OleDbCommand();
      //数据类型集合
      ArrayList DataTypeList = new ArrayList();
      DataTypeList.Add("System.Decimal");
      DataTypeList.Add("System.Double");
      DataTypeList.Add("System.Int16");
      DataTypeList.Add("System.Int32");
      DataTypeList.Add("System.Int64");
      DataTypeList.Add("System.Single");
      DataColumn col = new DataColumn();
      //遍历数据表的所有列，用于创建表结构
      for (int k = 0; k < ColCount; k++)
      {
        col = (DataColumn)Columns[k];
        //列的数据类型是数字型
        if (DataTypeList.IndexOf(col.DataType.ToString().Trim()) >= 0)
        {
          para[k] = new OleDbParameter("@" + col.Caption.Trim(), OleDbType.Double);
          objCmd.Parameters.Add(para[k]);
          //如果是最后一列
          if (k + 1 == ColCount)
          {
            TableStructStr += col.Caption.Trim() + " Double)";
          }
          else
          {
            TableStructStr += col.Caption.Trim() + " Double,";
          }
        }
        else
        {
          para[k] = new OleDbParameter("@" + col.Caption.Trim(), OleDbType.VarChar);
          objCmd.Parameters.Add(para[k]);
          //如果是最后一列
          if (k + 1 == ColCount)
          {
            TableStructStr += col.Caption.Trim() + " VarChar)";
          }
          else
          {
            TableStructStr += col.Caption.Trim() + " VarChar,";
          }
        }
      }
      //创建Excel文件及文件结构
      try
      {
        objCmd.Connection = objConn;
        objCmd.CommandText = TableStructStr;
        if (objConn.State == ConnectionState.Closed)
        {
          objConn.Open();
        }
        objCmd.ExecuteNonQuery();
      }
      catch (Exception exp)
      {
        throw exp;
      }
      //插入记录的SQL语句
      string InsertSql_1 = "Insert into " + Table.TableName + " (";
      string InsertSql_2 = " Values (";
      string InsertSql = "";
      //遍历所有列，用于插入记录，在此创建插入记录的SQL语句
      for (int colID = 0; colID < ColCount; colID++)
      {
        if (colID + 1 == ColCount) //最后一列
        {
          InsertSql_1 += Columns[colID].ToString().Trim() + ")";
          InsertSql_2 += "@" + Columns[colID].ToString().Trim() + ")";
        }
        else
        {
          InsertSql_1 += Columns[colID].ToString().Trim() + ",";
          InsertSql_2 += "@" + Columns[colID].ToString().Trim() + ",";
        }
      }
      InsertSql = InsertSql_1 + InsertSql_2;
      //遍历数据表的所有数据行
      DataColumn DataCol = new DataColumn();
      for (int rowID = 0; rowID < Table.Rows.Count; rowID++)
      {
        for (int colID = 0; colID < ColCount; colID++)
        {
          //因为列不连续，所以在取得单元格时不能用行列编号，列需得用列的名称
          DataCol = (DataColumn)Columns[colID];
          if (para[colID].DbType == DbType.Double && Table.Rows[rowID][DataCol.Caption].ToString().Trim() == "")
          {
            para[colID].Value = 0;
          }
          else
          {
            para[colID].Value = Table.Rows[rowID][DataCol.Caption].ToString().Trim();
          }
        }
        try
        {
          objCmd.CommandText = InsertSql;
          objCmd.ExecuteNonQuery();
        }
        catch (Exception exp)
        {
          string str = exp.Message;
        }
      }
      try
      {
        if (objConn.State == ConnectionState.Open)
        {
          objConn.Close();
        }
      }
      catch (Exception exp)
      {
        throw exp;
      }
      return true;
    }
    #endregion
    /// <summary>
    /// 获取Excel文件数据表列表
    /// </summary>
    public static ArrayList GetExcelTables(string ExcelFileName)
    {
      DataTable dt = new DataTable();
      ArrayList TablesList = new ArrayList();
      if (File.Exists(ExcelFileName))
      {
        using (OleDbConnection conn = new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Extended Properties=Excel 8.0;Data Source=" + ExcelFileName))
        {
          try
          {
            conn.Open();
            dt = conn.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, new object[] { null, null, null, "TABLE" });
          }
          catch (Exception exp)
          {
            throw exp;
          }
          //获取数据表个数
          int tablecount = dt.Rows.Count;
          for (int i = 0; i < tablecount; i++)
          {
            string tablename = dt.Rows[i][2].ToString().Trim().TrimEnd('$');
            if (TablesList.IndexOf(tablename) < 0)
            {
              TablesList.Add(tablename);
            }
          }
        }
      }
      return TablesList;
    }
    /// <summary>
    /// 将Excel文件导出至DataTable(第一行作为表头)
    /// </summary>
    /// <param name="ExcelFilePath">Excel文件路径</param>
    /// <param name="TableName">数据表名，如果数据表名错误，默认为第一个数据表名</param>
    public static DataTable InputFromExcel(string ExcelFilePath, string TableName)
    {
      if (!File.Exists(ExcelFilePath))
      {
        throw new Exception("Excel文件不存在！");
      }
      //如果数据表名不存在，则数据表名为Excel文件的第一个数据表
      ArrayList TableList = new ArrayList();
      TableList = GetExcelTables(ExcelFilePath);
      if (TableName.IndexOf(TableName) < 0)
      {
        TableName = TableList[0].ToString().Trim();
      }
      DataTable table = new DataTable();
      OleDbConnection dbcon = new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + ExcelFilePath + ";Extended Properties=Excel 8.0");
      OleDbCommand cmd = new OleDbCommand("select * from [" + TableName + "$]", dbcon);
      OleDbDataAdapter adapter = new OleDbDataAdapter(cmd);
      try
      {
        if (dbcon.State == ConnectionState.Closed)
        {
          dbcon.Open();
        }
        adapter.Fill(table);
      }
      catch (Exception exp)
      {
        throw exp;
      }
      finally
      {
        if (dbcon.State == ConnectionState.Open)
        {
          dbcon.Close();
        }
      }
      return table;
    }
    /// <summary>
    /// 获取Excel文件指定数据表的数据列表
    /// </summary>
    /// <param name="ExcelFileName">Excel文件名</param>
    /// <param name="TableName">数据表名</param>
    public static ArrayList GetExcelTableColumns(string ExcelFileName, string TableName)
    {
      DataTable dt = new DataTable();
      ArrayList ColsList = new ArrayList();
      if (File.Exists(ExcelFileName))
      {
        using (OleDbConnection conn = new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Extended Properties=Excel 8.0;Data Source=" + ExcelFileName))
        {
          conn.Open();
          dt = conn.GetOleDbSchemaTable(OleDbSchemaGuid.Columns, new object[] { null, null, TableName, null });
          //获取列个数
          int colcount = dt.Rows.Count;
          for (int i = 0; i < colcount; i++)
          {
            string colname = dt.Rows[i]["Column_Name"].ToString().Trim();
            ColsList.Add(colname);
          }
        }
      }
      return ColsList;
    }
  }
}