雜七雜八DataTable獲取Table某一列成List轉換Table成List

        public static List<T> GetColumnValues<T>(DataTable dtSource, string filedName)
        {
            return (from r in dtSource.AsEnumerable() select r.Field<T>(filedName)).ToList<T>();
        }

獲取table某一列的數據轉換成list

  List<AHPResult> AHPResult = DatableToList<AHPResult>(dResulttable,year.ToString());

      public static List<T> DatableToList<T>(DataTable dt,string Time) where T : class, new()
        {

            Type type = typeof(T);
            List<T> oblist = new List<T>();
            string tempName = string.Empty;
            foreach (DataRow row in dt.Rows)
            {

                T t = new T();
                PropertyInfo[] propertys = t.GetType().GetProperties();
                foreach (PropertyInfo pi in propertys)
                {
                    tempName = (pi.GetCustomAttributes(false)[0] as Property).Value;
                    if (dt.Columns.Contains(tempName))
                    {
                        if (!pi.CanWrite) continue;//該屬性不可寫，直接跳出
                        object value = row[tempName];
                        if (value != DBNull.Value)
                            pi.SetValue(t, value, null);


                    }
                    if(tempName=="時間")
                    {
                        pi.SetValue(t, Time+"年", null);
                    }
                }

                oblist.Add(t);
            }
            return oblist;
        }

    public class AHPResult
    {
       // public string AreaCode { get; set; }

        [Property("時間")]
        public string Time { get; set; }

        [Property("評價目標")]
        public string Area { get; set; }

        [Property("綜合得分")]
        public string IndicatorData { get; set; }
        [Property("排名")]
        public string Rank { get; set; }
    }
    class Property : System.Attribute
    {
        public string Value { get; set; }

        public Property(string Value)
        {
            this.Value = Value;
        }
    }

將table轉換成統一的List<Model> 列名和屬性名映射。

using System.Text;
using System.IO;
using NPOI.SS.UserModel;        //NPOI
using NPOI.HSSF.Util;           //NPOI
using NPOI.HSSF.UserModel;      //NPOI
using NPOI.XSSF.UserModel;      //NPOI
using System.Data;
namespace LNERI_P2_WebApi.Common
{
    public class ExcelHelper
    {
        public static DataTable ExcelSheetImportToDataTable(string filePath)
        {

            DataTable dt = new DataTable();
            IWorkbook hssfworkbook;         
            if (Path.GetExtension(filePath).ToLower() == ".xls".ToLower())
            {//.xls
                #region .xls文件處理:HSSFWorkbook
                try
                {
                    using (FileStream file = new FileStream(filePath, FileMode.Open, FileAccess.Read))
                    {

                        hssfworkbook = new HSSFWorkbook(file);
                    }
                }
                catch (Exception e)
                {
                    LogHelper.Debug(e.InnerException + e.Message + e.Source + e.StackTrace + e.TargetSite);
                    throw e;
                }

                ISheet sheet = hssfworkbook.GetSheetAt(0);
                System.Collections.IEnumerator rows = sheet.GetRowEnumerator();
                HSSFRow headerRow = (HSSFRow)sheet.GetRow(0);

                //一行最後一個方格的編號 即總的列數 
                for (int j = 0; j < (sheet.GetRow(0).LastCellNum); j++)
                {
                    //SET EVERY COLUMN NAME
                    HSSFCell cell = (HSSFCell)headerRow.GetCell(j);

                    dt.Columns.Add(cell.ToString());
                }

                while (rows.MoveNext())
                {
                    IRow row = (HSSFRow)rows.Current;
                    DataRow dr = dt.NewRow();

                    if (row.RowNum == 0) continue;//The firt row is title,no need import
                    if (row == null)
                    {
                        continue;
                    }
                    bool insert = true;
                    for (int i = 0; i < row.LastCellNum; i++)
                    {
                        if (i >= dt.Columns.Count)//cell count>column count,then break //每條記錄的單元格數量不能大於表格欄位數量 20140213
                        {
                            insert = false;
                            break;
                        }
                        if (row.LastCellNum != 6)
                        {
                            insert = false;
                            break;
                        }
                        ICell cell = row.GetCell(i);

                        if ((i == 0) && (string.IsNullOrEmpty(cell.ToString()) == true))//每行第一個cell爲空,break
                        {
                            insert = false;
                            break;
                        }

                        if (cell == null)
                        {
                            dr[i] = null;
                        }
                        else
                        {
                            if (i == 0 && cell.CellType == CellType.Numeric)
                            {
                                dr[i] = cell.DateCellValue.Date.ToLongDateString();
                            }
                            else
                            {
                                dr[i] = cell.ToString();
                            }
                        }
                    }
                    if (insert == true)
                    {
                        dt.Rows.Add(dr);
                    }
                }
                #endregion
            }
            else
            {//.xlsx
                #region .xlsx文件處理:XSSFWorkbook
                try
                {
                    using (FileStream file = new FileStream(filePath, FileMode.Open, FileAccess.Read))
                    {

                        hssfworkbook = new XSSFWorkbook(file);
                    }
                }
                catch (Exception e)
                {
                    LogHelper.Debug(e.InnerException + e.Message + e.Source + e.StackTrace + e.TargetSite);
                    throw e;
                }

                ISheet sheet = hssfworkbook.GetSheetAt(0);
                System.Collections.IEnumerator rows = sheet.GetRowEnumerator();
                XSSFRow headerRow = (XSSFRow)sheet.GetRow(0);



                //一行最後一個方格的編號 即總的列數  
                for (int j = 0; j < (sheet.GetRow(0).LastCellNum); j++)
                {
                    //SET EVERY COLUMN NAME
                    XSSFCell cell = (XSSFCell)headerRow.GetCell(j);

                    dt.Columns.Add(cell.ToString());

                }

                while (rows.MoveNext())
                {
                    IRow row = (XSSFRow)rows.Current;
                    DataRow dr = dt.NewRow();

                    if (row.RowNum == 0) continue;//The firt row is title,no need import

                    for (int i = 0; i < row.LastCellNum; i++)
                    {
                        if (i >= dt.Columns.Count)//cell count>column count,then break //每條記錄的單元格數量不能大於表格欄位數量 20140213
                        {
                            break;
                        }

                        ICell cell = row.GetCell(i);

                        if ((i == 0) && (string.IsNullOrEmpty(cell.ToString()) == true))//每行第一個cell爲空,break
                        {
                            break;
                        }

                        if (cell == null)
                        {
                            dr[i] = null;
                        }
                        else
                        {
                            dr[i] = cell.ToString();
                        }
                    }
                    dt.Rows.Add(dr);
                }
                #endregion
            }
            return dt;
        }

        public static DataTable ExcelToDataTable(string filePath, bool isColumnName)
        {
            DataTable dataTable = null;
            FileStream fs = null;
            DataColumn column = null;
            DataRow dataRow = null;
            IWorkbook workbook = null;
            ISheet sheet = null;
            IRow row = null;
            ICell cell = null;
            int startRow = 0;
           // LogHelper.Debug(filePath);
            try
            {
                using (fs = new FileStream(filePath, FileMode.Open, FileAccess.Read))
                {
                    // 2007版本  

                    if (filePath.IndexOf(".xlsx") > 0)
                    { 
                        workbook = new XSSFWorkbook(fs);

                    }
                    // 2003版本  
                    else if (filePath.IndexOf(".xls") > 0)
                    {
                        workbook = new HSSFWorkbook(fs);
                    }

                    if (workbook != null)
                    {
                        sheet = workbook.GetSheetAt(0);//讀取第一個sheet，固然也能夠循環讀取每一個sheet  
                        dataTable = new DataTable();
                        if (sheet != null)
                        {
                            int rowCount = sheet.LastRowNum;//總行數  
                            if (rowCount > 0)
                            {
                                IRow firstRow = sheet.GetRow(0);//第一行  
                                int cellCount = firstRow.LastCellNum;//列數  

                                //構建datatable的列  
                                if (isColumnName)
                                {
                                    startRow = 1;//若是第一行是列名，則從第二行開始讀取  
                                    for (int i = firstRow.FirstCellNum; i < cellCount; ++i)
                                    {
                                        cell = firstRow.GetCell(i);
                                        if (cell != null)
                                        {
                                            if (cell.StringCellValue != null)
                                            {
                                                column = new DataColumn(cell.StringCellValue);
                                                dataTable.Columns.Add(column);
                                            }
                                        }
                                    }
                                }
                                else
                                {
                                    for (int i = firstRow.FirstCellNum; i < cellCount; ++i)
                                    {
                                        column = new DataColumn("column" + (i + 1));
                                        dataTable.Columns.Add(column);
                                    }
                                }

                                //填充行  
                                for (int i = startRow; i <= rowCount; ++i)
                                {
                                    row = sheet.GetRow(i);
                                    if (row == null) continue;

                                    dataRow = dataTable.NewRow();
                                    for (int j = row.FirstCellNum; j < cellCount; ++j)
                                    {
                                        cell = row.GetCell(j);
                                        if (cell == null)
                                        {
                                            dataRow[j] = "";
                                        }
                                        else
                                        {
                                            //CellType(Unknown = -1,Numeric = 0,String = 1,Formula = 2,Blank = 3,Boolean = 4,Error = 5,)  
                                            switch (cell.CellType)
                                            {
                                                case CellType.Blank:
                                                    dataRow[j] = "";
                                                    break;
                                                case CellType.Numeric:
                                                    short format = cell.CellStyle.DataFormat;
                                                    //對時間格式（2015.12.五、2015/12/五、2015-12-5等）的處理  
                                                    if (format == 14 || format == 31 || format == 57 || format == 58)
                                                        dataRow[j] = cell.DateCellValue;
                                                    else
                                                        dataRow[j] = cell.NumericCellValue;
                                                    break;
                                                case CellType.String:
                                                    dataRow[j] = cell.StringCellValue;
                                                    break;
                                            }
                                        }
                                    }
                                    dataTable.Rows.Add(dataRow);
                                }
                            }
                        }
                    }
                }
                return dataTable;
            }
            catch (Exception ex)
            {
                LogHelper.Debug("err：ExcelHelper.ExcelToDataTable" + ex.InnerException + ex.Message + ex.Source + ex.StackTrace + ex.TargetSite);

                if (fs != null)
                {
                    fs.Close();
                }
                return null;
            }
        }

    }
}

讀取excel文件成DataTable。