ExcelHelper

using System;
using System.Collections.Generic;
using System.Web;
using System.Web.UI.WebControls;
using System.IO;
using System.Data;
using System.Data.OleDb;
using System.Collections;
using System.Web.UI;

namespace Mujinsoft.CM.Core.Helpers
{
    public static class ExcelHelper
    {
        /// <summary>
        /// 获取Excel数据表列表
        /// </summary>
        /// <param name="ExcelFileName"></param>
        /// <returns></returns>
        public static ArrayList GetExcelTables(string ExcelFileName)
        {
            //将Excel架构存入数据里
            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>
        /// 获取指定Excel文件数据表的数据列列表
        /// </summary>
        /// <param name="ExcelFileName">Excel文件名</param>
        /// <param name="TableName">数据表名</param>
        /// <returns></returns>
        public static ArrayList GetExcelTableColumns(string ExcelFileName, string TableName)
        {
            //将Excel架构存入数据里
            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;
        }

        /// <summary>
        /// 获取指定Excel文件数据表的数据列列表
        /// </summary>
        /// <param name="ExcelFileName">Excel文件名</param>
        /// <param name="TableName">数据表名</param>
        /// <returns></returns>
        public static DataTable GetExcelTable(string ExcelFileName, string TableName)
        {
            //将Excel架构存入数据里
            DataTable dt = new DataTable();
            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 });
                }
            }
            return dt;
        }




        /// <summary>
        /// 将数据导出至Excel
        /// </summary>
        /// <param name="Table">DataTable对象</param>
        /// <param name="ExcelFilePath">Excel文件路径</param>
        /// <returns></returns>
        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
        /// </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>
        /// <returns></returns>
        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;
            //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");

            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;
        }


        /// <summary>
        /// 导入Excel数据表至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>
        /// <returns></returns>
        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，数据表名为Excel文件的第一个数据表
            ArrayList TableList = new ArrayList();
            TableList = ExcelHelper.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;
        }

        #region  调用前注意事项
        //必须将页面的EnableEventValidation属性设为false
        //必须履盖页面的VerifyRenderingInServerForm方法
        #endregion


        #region  GridView导出到Excel静态方法
        public static void ToExcelGridView(GridView gdView, string FileName)
        {
            HttpContext.Current.Response.Clear();
            HttpContext.Current.Response.Buffer = true;
            HttpContext.Current.Response.Write("<meta http-equiv=Content-Type content=text/html;charset=gb2312>");
            HttpContext.Current.Response.AppendHeader("Content-Disposition", "attachment;filename=" + System.Web.HttpUtility.UrlEncode(FileName, System.Text.Encoding.UTF8) + ".xls");
            HttpContext.Current.Response.ContentEncoding = System.Text.Encoding.GetEncoding("GB2312");//设置输出流为简体中文
            HttpContext.Current.Response.ContentType = "application/ms-excel";//设置输出文件类型为excel文件。 


            gdView.EnableViewState = false;
            System.Globalization.CultureInfo myCItrad = new System.Globalization.CultureInfo("ZH-CN", true);
            System.IO.StringWriter oStringWriter = new System.IO.StringWriter(myCItrad);
            System.Web.UI.HtmlTextWriter oHtmlTextWriter = new System.Web.UI.HtmlTextWriter(oStringWriter);
            gdView.RenderControl(oHtmlTextWriter);
            HttpContext.Current.Response.Write(oStringWriter.ToString());
            HttpContext.Current.Response.End();

        }
        #endregion

        #region FormView导出到Excel静态方法
        public static void ToExcelFormView(FormView formView)
        {
            HttpContext.Current.Response.Clear();
            HttpContext.Current.Response.Buffer = true;
            HttpContext.Current.Response.Charset = "GB2312";
            HttpContext.Current.Response.AppendHeader("Content-Disposition", "attachment;filename=FileName.xls");
            HttpContext.Current.Response.ContentEncoding = System.Text.Encoding.GetEncoding("utf-7");//设置输出流为简体中文
            HttpContext.Current.Response.ContentType = "application/ms-excel";//设置输出文件类型为excel文件。 

            formView.EnableViewState = false;
            System.Globalization.CultureInfo myCItrad = new System.Globalization.CultureInfo("ZH-CN", true);
            System.IO.StringWriter oStringWriter = new System.IO.StringWriter(myCItrad);
            System.Web.UI.HtmlTextWriter oHtmlTextWriter = new System.Web.UI.HtmlTextWriter(oStringWriter);
            formView.RenderControl(oHtmlTextWriter);
            HttpContext.Current.Response.Write(oStringWriter.ToString());
            HttpContext.Current.Response.End();
        }

        #endregion

        public static void ToExcelDataSet(DataSet ds, string FileName)
        {
            GridView gdView = new GridView();
            gdView.DataSource = ds.Tables[0].DefaultView;
            gdView.DataBind();
            ToExcelGridView(gdView, FileName);
        }

        public static void ToExcelList<T>(List<T> list, string FileName)
        {
            GridView gdView = new GridView();
            gdView.DataSource = DataHelper.ToDataTable<T>(list);
            gdView.DataBind();
            ToExcelGridView(gdView, FileName);
        }

        public static void ToExcelDataSet<T>(IList<T> ds, string FileName)
        {
            GridView gdView = new GridView();
            gdView.DataSource = ds;
            gdView.DataBind();
            ToExcelGridView(gdView, FileName);
        }

        #region  GridView导出到Excel静态方法
        public static void ToExcelRepeater(Repeater gdView, string FileName)
        {
            HttpContext.Current.Response.Clear();
            HttpContext.Current.Response.Buffer = true;
            HttpContext.Current.Response.Write("<meta http-equiv=Content-Type content=text/html;charset=gb2312>");
            HttpContext.Current.Response.AppendHeader("Content-Disposition", "attachment;filename=" + System.Web.HttpUtility.UrlEncode(FileName, System.Text.Encoding.UTF8) + ".xls");
            HttpContext.Current.Response.ContentEncoding = System.Text.Encoding.GetEncoding("GB2312");//设置输出流为简体中文
            HttpContext.Current.Response.ContentType = "application/ms-excel";//设置输出文件类型为excel文件。 


            gdView.EnableViewState = false;
            System.Globalization.CultureInfo myCItrad = new System.Globalization.CultureInfo("ZH-CN", true);
            System.IO.StringWriter oStringWriter = new System.IO.StringWriter(myCItrad);
            System.Web.UI.HtmlTextWriter oHtmlTextWriter = new System.Web.UI.HtmlTextWriter(oStringWriter);
            gdView.RenderControl(oHtmlTextWriter);
            HttpContext.Current.Response.Write(oStringWriter.ToString());
            HttpContext.Current.Response.End();

        }
        #endregion


        

        #region 将数据导入Excel
        /// <summary>
        /// 获取Excel文件数据表列表
        /// </summary>
        public static ArrayList FromExcel(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 FromExcel(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 = FromExcel(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;
        }

        #endregion

        public static DataTable GetExcelToDataTableBySheet(string FileFullPath, string SheetName)
        {
            string strConn = "Provider=Microsoft.Jet.OleDb.4.0;" + "data source=" + FileFullPath + ";Extended Properties='Excel 8.0; HDR=NO; IMEX=1'"; //此连接只能操作Excel2007之前(.xls)文件
            //string strConn = "Provider=Microsoft.Ace.OleDb.12.0;" + "data source=" + FileFullPath + ";Extended Properties='Excel 12.0; HDR=NO; IMEX=1'"; //此连接可以操作.xls与.xlsx文件
            OleDbConnection conn = new OleDbConnection(strConn);
            conn.Open();
            DataSet ds = new DataSet();
            OleDbDataAdapter odda = new OleDbDataAdapter(string.Format("SELECT * FROM [{0}$]", SheetName), conn);                    //("select * from [Sheet1$]", conn);
            odda.Fill(ds, SheetName);
            conn.Close();
            return ds.Tables[0];

        }

        #region 导出Excel文件，自动返回可下载的文件流
        /// 导出Excel文件，自动返回可下载的文件流 
        public static void DataTableExcel(System.Data.DataTable dtData, string FileName)
        {
            HttpContext.Current.Response.Clear();
            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.Write("<meta http-equiv=Content-Type content=text/html;charset=utf-8>");
                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 = "utf-8";
                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();
            }
        }
        #endregion
    }
}

原文地址：http://www.cnblogs.com/Mr-King/p/4000020.html