Excel导入导出DataGridView

  /// <summary>
         /// excel表保存到dataTable中
         /// </summary>
         /// <param name="path">excel表路径</param>
         /// <returns>返回第一个sheet表</returns>
         private static DataTable ExcelToDataTable(string path)
         {
             DataTable dt = new DataTable();
             try
             {
                 //连接字符串
                 string connstring = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + path + ";Extended Properties='Excel 8.0;HDR=NO;IMEX=1';"; // Office 07及以上版本 不能出现多余的空格 而且分号注意
                 //string connstring = Provider=Microsoft.JET.OLEDB.4.0;Data Source=" + path + ";Extended Properties='Excel 8.0;HDR=NO;IMEX=1';"; //Office 07以下版本
                 using (OleDbConnection conn = new OleDbConnection(connstring))
                 {
                     conn.Open();
                     DataTable sheetsName = conn.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, new object[] { null, null, null, "Table" }); //得到所有sheet的名字
                     string firstSheetName = sheetsName.Rows[][].ToString(); //得到第一个sheet的名字
                     string sql = string.Format("SELECT * FROM [{0}]", firstSheetName); //查询字符串
                     //string sql = string.Format("SELECT * FROM [{0}] WHERE [日期] is not null", firstSheetName); //查询字符串
                     OleDbDataAdapter ada = new OleDbDataAdapter(sql, connstring);
                     DataSet set = new DataSet();
                     ada.Fill(set);
                     dt = set.Tables[];
                 }
                 return dt;
             }
             catch (Exception ex)
             {
                 MessageBox.Show(ex.Message);
                 return null;
             }
         }

/// <summary>
        /// excel表保存到dataTable中
        /// </summary>
        /// <param name="path">excel表路径</param>
        /// <returns>返回第一个sheet表</returns>
        private static DataTable ExcelToDataTable(string path)
        {
            DataTable dt = new DataTable();
            try
            {
                //连接字符串    
                string connstring = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + path + ";Extended Properties='Excel 8.0;HDR=NO;IMEX=1';"; // Office 07及以上版本 不能出现多余的空格 而且分号注意         
                //string connstring = Provider=Microsoft.JET.OLEDB.4.0;Data Source=" + path + ";Extended Properties='Excel 8.0;HDR=NO;IMEX=1';"; //Office 07以下版本    
                using (OleDbConnection conn = new OleDbConnection(connstring))
                {
                    conn.Open();
                    DataTable sheetsName = conn.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, new object[] { null, null, null, "Table" }); //得到所有sheet的名字  
                    string firstSheetName = sheetsName.Rows[0][2].ToString(); //得到第一个sheet的名字     
                    string sql = string.Format("SELECT * FROM [{0}]", firstSheetName); //查询字符串 
                    //string sql = string.Format("SELECT * FROM [{0}] WHERE [日期] is not null", firstSheetName); //查询字符串  
                    OleDbDataAdapter ada = new OleDbDataAdapter(sql, connstring);
                    DataSet set = new DataSet();
                    ada.Fill(set);
                    dt = set.Tables[0];
                }
                return dt;
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
                return null;
            }
        }

         /// <summary>
         /// excel表保存到dataTable中
         /// </summary>
         /// <param name="path">excel表路径</param>
         /// <returns>返回第一个sheet表</returns>
         private static DataTable ExcelToDataTable(string path)
         {
             DataTable dt = new DataTable();
             try
             {
                 //连接字符串
                 string connstring = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + path + ";Extended Properties='Excel 8.0;HDR=NO;IMEX=1';"; // Office 07及以上版本 不能出现多余的空格 而且分号注意
                 //string connstring = Provider=Microsoft.JET.OLEDB.4.0;Data Source=" + path + ";Extended Properties='Excel 8.0;HDR=NO;IMEX=1';"; //Office 07以下版本
                 using (OleDbConnection conn = new OleDbConnection(connstring))
                 {
                     conn.Open();
                     DataTable sheetsName = conn.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, new object[] { null, null, null, "Table" }); //得到所有sheet的名字
                     string firstSheetName = sheetsName.Rows[][].ToString(); //得到第一个sheet的名字
                     string sql = string.Format("SELECT * FROM [{0}]", firstSheetName); //查询字符串
                     //string sql = string.Format("SELECT * FROM [{0}] WHERE [日期] is not null", firstSheetName); //查询字符串
                     OleDbDataAdapter ada = new OleDbDataAdapter(sql, connstring);
                     DataSet set = new DataSet();
                     ada.Fill(set);
                     dt = set.Tables[];
                 }
                 return dt;
             }
             catch (Exception ex)
             {
                 MessageBox.Show(ex.Message);
                 return null;
             }
         }

网上查找的方法，忘记在哪找的了，在这记录下：

/// <summary>
        /// excel表保存到dataTable中
        /// </summary>
        /// <param name="path">excel表路径</param>
        /// <returns>返回第一个sheet表</returns>
        private static DataTable ExcelToDataTable(string path)
        {
            DataTable dt = new DataTable();
            try
            {
                //连接字符串    
                string connstring = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + path + ";Extended Properties='Excel 8.0;HDR=NO;IMEX=1';"; // Office 07及以上版本 不能出现多余的空格 而且分号注意         
                //string connstring = Provider=Microsoft.JET.OLEDB.4.0;Data Source=" + path + ";Extended Properties='Excel 8.0;HDR=NO;IMEX=1';"; //Office 07以下版本    
                using (OleDbConnection conn = new OleDbConnection(connstring))
                {
                    conn.Open();
                    DataTable sheetsName = conn.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, new object[] { null, null, null, "Table" }); //得到所有sheet的名字  
                    string firstSheetName = sheetsName.Rows[0][2].ToString(); //得到第一个sheet的名字     
                    string sql = string.Format("SELECT * FROM [{0}]", firstSheetName); //查询字符串 
                    //string sql = string.Format("SELECT * FROM [{0}] WHERE [日期] is not null", firstSheetName); //查询字符串  
                    OleDbDataAdapter ada = new OleDbDataAdapter(sql, connstring);
                    DataSet set = new DataSet();
                    ada.Fill(set);
                    dt = set.Tables[0];
                }
                return dt;
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
                return null;
            }
        }